clauses.c File Reference

#include "postgres.h"
#include "access/htup_details.h"
#include "catalog/pg_class.h"
#include "catalog/pg_language.h"
#include "catalog/pg_operator.h"
#include "catalog/pg_proc.h"
#include "catalog/pg_type.h"
#include "executor/executor.h"
#include "executor/functions.h"
#include "funcapi.h"
#include "miscadmin.h"
#include "nodes/makefuncs.h"
#include "nodes/multibitmapset.h"
#include "nodes/nodeFuncs.h"
#include "nodes/subscripting.h"
#include "nodes/supportnodes.h"
#include "optimizer/clauses.h"
#include "optimizer/cost.h"
#include "optimizer/optimizer.h"
#include "optimizer/pathnode.h"
#include "optimizer/plancat.h"
#include "optimizer/planmain.h"
#include "parser/analyze.h"
#include "parser/parse_coerce.h"
#include "parser/parse_collate.h"
#include "parser/parse_func.h"
#include "parser/parse_oper.h"
#include "parser/parsetree.h"
#include "rewrite/rewriteHandler.h"
#include "rewrite/rewriteManip.h"
#include "tcop/tcopprot.h"
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/datum.h"
#include "utils/fmgroids.h"
#include "utils/json.h"
#include "utils/jsonb.h"
#include "utils/jsonpath.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/syscache.h"
#include "utils/typcache.h"

Include dependency graph for clauses.c:

Go to the source code of this file.

Data Structures
struct	eval_const_expressions_context
struct	substitute_actual_parameters_context
struct	substitute_actual_srf_parameters_context
struct	inline_error_callback_arg
struct	max_parallel_hazard_context

Macros
#define	CCDN_CASETESTEXPR_OK   0x0001 /* CaseTestExpr okay here? */
#define	MIN_ARRAY_SIZE_FOR_HASHED_SAOP   9
#define	ece_generic_processing(node)
#define	ece_all_arguments_const(node)    (!expression_tree_walker((Node *) (node), contain_non_const_walker, NULL))
#define	ece_evaluate_expr(node)

Functions
static bool	contain_agg_clause_walker (Node *node, void *context)
static bool	find_window_functions_walker (Node *node, WindowFuncLists *lists)
static bool	contain_subplans_walker (Node *node, void *context)
static bool	contain_mutable_functions_walker (Node *node, void *context)
static bool	contain_volatile_functions_walker (Node *node, void *context)
static bool	contain_volatile_functions_not_nextval_walker (Node *node, void *context)
static bool	max_parallel_hazard_walker (Node *node, max_parallel_hazard_context *context)
static bool	contain_nonstrict_functions_walker (Node *node, void *context)
static bool	contain_exec_param_walker (Node *node, List *param_ids)
static bool	contain_context_dependent_node (Node *clause)
static bool	contain_context_dependent_node_walker (Node *node, int *flags)
static bool	contain_leaked_vars_walker (Node *node, void *context)
static Relids	find_nonnullable_rels_walker (Node *node, bool top_level)
static List *	find_nonnullable_vars_walker (Node *node, bool top_level)
static bool	is_strict_saop (ScalarArrayOpExpr *expr, bool falseOK)
static bool	convert_saop_to_hashed_saop_walker (Node *node, void *context)
static Node *	eval_const_expressions_mutator (Node *node, eval_const_expressions_context *context)
static bool	contain_non_const_walker (Node *node, void *context)
static bool	ece_function_is_safe (Oid funcid, eval_const_expressions_context *context)
static List *	simplify_or_arguments (List *args, eval_const_expressions_context *context, bool *haveNull, bool *forceTrue)
static List *	simplify_and_arguments (List *args, eval_const_expressions_context *context, bool *haveNull, bool *forceFalse)
static Node *	simplify_boolean_equality (Oid opno, List *args)
static Expr *	simplify_function (Oid funcid, Oid result_type, int32 result_typmod, Oid result_collid, Oid input_collid, List **args_p, bool funcvariadic, bool process_args, bool allow_non_const, eval_const_expressions_context *context)
static List *	reorder_function_arguments (List *args, int pronargs, HeapTuple func_tuple)
static List *	add_function_defaults (List *args, int pronargs, HeapTuple func_tuple)
static List *	fetch_function_defaults (HeapTuple func_tuple)
static void	recheck_cast_function_args (List *args, Oid result_type, Oid *proargtypes, int pronargs, HeapTuple func_tuple)
static Expr *	evaluate_function (Oid funcid, Oid result_type, int32 result_typmod, Oid result_collid, Oid input_collid, List *args, bool funcvariadic, HeapTuple func_tuple, eval_const_expressions_context *context)
static Expr *	inline_function (Oid funcid, Oid result_type, Oid result_collid, Oid input_collid, List *args, bool funcvariadic, HeapTuple func_tuple, eval_const_expressions_context *context)
static Node *	substitute_actual_parameters (Node *expr, int nargs, List *args, int *usecounts)
static Node *	substitute_actual_parameters_mutator (Node *node, substitute_actual_parameters_context *context)
static void	sql_inline_error_callback (void *arg)
static Query *	substitute_actual_srf_parameters (Query *expr, int nargs, List *args)
static Node *	substitute_actual_srf_parameters_mutator (Node *node, substitute_actual_srf_parameters_context *context)
static bool	pull_paramids_walker (Node *node, Bitmapset **context)
bool	contain_agg_clause (Node *clause)
bool	contain_window_function (Node *clause)
WindowFuncLists *	find_window_functions (Node *clause, Index maxWinRef)
double	expression_returns_set_rows (PlannerInfo *root, Node *clause)
bool	contain_subplans (Node *clause)
bool	contain_mutable_functions (Node *clause)
static bool	contain_mutable_functions_checker (Oid func_id, void *context)
bool	contain_mutable_functions_after_planning (Expr *expr)
bool	contain_volatile_functions (Node *clause)
static bool	contain_volatile_functions_checker (Oid func_id, void *context)
bool	contain_volatile_functions_after_planning (Expr *expr)
bool	contain_volatile_functions_not_nextval (Node *clause)
static bool	contain_volatile_functions_not_nextval_checker (Oid func_id, void *context)
char	max_parallel_hazard (Query *parse)
bool	is_parallel_safe (PlannerInfo *root, Node *node)
static bool	max_parallel_hazard_test (char proparallel, max_parallel_hazard_context *context)
static bool	max_parallel_hazard_checker (Oid func_id, void *context)
bool	contain_nonstrict_functions (Node *clause)
static bool	contain_nonstrict_functions_checker (Oid func_id, void *context)
bool	contain_exec_param (Node *clause, List *param_ids)
bool	contain_leaked_vars (Node *clause)
static bool	contain_leaked_vars_checker (Oid func_id, void *context)
Relids	find_nonnullable_rels (Node *clause)
List *	find_nonnullable_vars (Node *clause)
List *	find_forced_null_vars (Node *node)
Var *	find_forced_null_var (Node *node)
bool	is_pseudo_constant_clause (Node *clause)
bool	is_pseudo_constant_clause_relids (Node *clause, Relids relids)
int	NumRelids (PlannerInfo *root, Node *clause)
void	CommuteOpExpr (OpExpr *clause)
static bool	rowtype_field_matches (Oid rowtypeid, int fieldnum, Oid expectedtype, int32 expectedtypmod, Oid expectedcollation)
Node *	eval_const_expressions (PlannerInfo *root, Node *node)
void	convert_saop_to_hashed_saop (Node *node)
Node *	estimate_expression_value (PlannerInfo *root, Node *node)
bool	var_is_nonnullable (PlannerInfo *root, Var *var, bool use_rel_info)
List *	expand_function_arguments (List *args, bool include_out_arguments, Oid result_type, HeapTuple func_tuple)
Expr *	evaluate_expr (Expr *expr, Oid result_type, int32 result_typmod, Oid result_collation)
Query *	inline_set_returning_function (PlannerInfo *root, RangeTblEntry *rte)
Bitmapset *	pull_paramids (Expr *expr)
ScalarArrayOpExpr *	make_SAOP_expr (Oid oper, Node *leftexpr, Oid coltype, Oid arraycollid, Oid inputcollid, List *exprs, bool haveNonConst)

Macro Definition Documentation

CCDN_CASETESTEXPR_OK

#define CCDN_CASETESTEXPR_OK   0x0001 /* CaseTestExpr okay here? */

Definition at line 1192 of file clauses.c.

ece_all_arguments_const

#define ece_all_arguments_const

(

node

)

(!expression_tree_walker((Node *) (node), contain_non_const_walker, NULL))

Definition at line 2434 of file clauses.c.

ece_evaluate_expr

#define ece_evaluate_expr

(

node

)

Value:

    ((Node *) evaluate_expr((Expr *) (node), \
                            exprType((Node *) (node)), \
                            exprTypmod((Node *) (node)), \
                            exprCollation((Node *) (node))))

Definition at line 2438 of file clauses.c.

ece_generic_processing

#define ece_generic_processing

(

node

)

Value:

    expression_tree_mutator((Node *) (node), eval_const_expressions_mutator, \
                            context)

Definition at line 2425 of file clauses.c.

MIN_ARRAY_SIZE_FOR_HASHED_SAOP

#define MIN_ARRAY_SIZE_FOR_HASHED_SAOP   9

Definition at line 2277 of file clauses.c.

Function Documentation

add_function_defaults()

static List * add_function_defaults ( List *  args, int  pronargs, HeapTuple  func_tuple  )

static

Definition at line 4430 of file clauses.c.

{
    int         nargsprovided = list_length(args);
    List       *defaults;
    int         ndelete;
 
    /* Get all the default expressions from the pg_proc tuple */
    defaults = fetch_function_defaults(func_tuple);
 
    /* Delete any unused defaults from the list */
    ndelete = nargsprovided + list_length(defaults) - pronargs;
    if (ndelete < 0)
        elog(ERROR, "not enough default arguments");
    if (ndelete > 0)
        defaults = list_delete_first_n(defaults, ndelete);
 
    /* And form the combined argument list, not modifying the input list */
    return list_concat_copy(args, defaults);
}

References generate_unaccent_rules::args, elog, ERROR, fetch_function_defaults(), list_concat_copy(), list_delete_first_n(), list_length(), and pronargs.

Referenced by expand_function_arguments().

CommuteOpExpr()

void CommuteOpExpr

(

OpExpr *

clause

)

Definition at line 2154 of file clauses.c.

{
    Oid         opoid;
    Node       *temp;
 
    /* Sanity checks: caller is at fault if these fail */
    if (!is_opclause(clause) ||
        list_length(clause->args) != 2)
        elog(ERROR, "cannot commute non-binary-operator clause");
 
    opoid = get_commutator(clause->opno);
 
    if (!OidIsValid(opoid))
        elog(ERROR, "could not find commutator for operator %u",
             clause->opno);
 
    /*
     * modify the clause in-place!
     */
    clause->opno = opoid;
    clause->opfuncid = InvalidOid;
    /* opresulttype, opretset, opcollid, inputcollid need not change */
 
    temp = linitial(clause->args);
    linitial(clause->args) = lsecond(clause->args);
    lsecond(clause->args) = temp;
}

References OpExpr::args, elog, ERROR, get_commutator(), InvalidOid, is_opclause(), linitial, list_length(), lsecond, OidIsValid, and OpExpr::opno.

Referenced by get_switched_clauses().

contain_agg_clause()

bool contain_agg_clause

(

Node *

clause

)

Definition at line 182 of file clauses.c.

{
    return contain_agg_clause_walker(clause, NULL);
}

References contain_agg_clause_walker().

Referenced by get_eclass_for_sort_expr(), mark_nullable_by_grouping(), and subquery_planner().

contain_agg_clause_walker()

static bool contain_agg_clause_walker ( Node *  node, void *  context  )

static

Definition at line 188 of file clauses.c.

{
    if (node == NULL)
        return false;
    if (IsA(node, Aggref))
    {
        Assert(((Aggref *) node)->agglevelsup == 0);
        return true;            /* abort the tree traversal and return true */
    }
    if (IsA(node, GroupingFunc))
    {
        Assert(((GroupingFunc *) node)->agglevelsup == 0);
        return true;            /* abort the tree traversal and return true */
    }
    Assert(!IsA(node, SubLink));
    return expression_tree_walker(node, contain_agg_clause_walker, context);
}

References Assert(), contain_agg_clause_walker(), expression_tree_walker, and IsA.

Referenced by contain_agg_clause(), and contain_agg_clause_walker().

contain_context_dependent_node()

static bool contain_context_dependent_node ( Node *  clause )

static

Definition at line 1185 of file clauses.c.

{
    int         flags = 0;
 
    return contain_context_dependent_node_walker(clause, &flags);
}

References contain_context_dependent_node_walker().

Referenced by inline_function().

contain_context_dependent_node_walker()

static bool contain_context_dependent_node_walker ( Node *  node, int *  flags  )

static

Definition at line 1195 of file clauses.c.

{
    if (node == NULL)
        return false;
    if (IsA(node, CaseTestExpr))
        return !(*flags & CCDN_CASETESTEXPR_OK);
    else if (IsA(node, CaseExpr))
    {
        CaseExpr   *caseexpr = (CaseExpr *) node;
 
        /*
         * If this CASE doesn't have a test expression, then it doesn't create
         * a context in which CaseTestExprs should appear, so just fall
         * through and treat it as a generic expression node.
         */
        if (caseexpr->arg)
        {
            int         save_flags = *flags;
            bool        res;
 
            /*
             * Note: in principle, we could distinguish the various sub-parts
             * of a CASE construct and set the flag bit only for some of them,
             * since we are only expecting CaseTestExprs to appear in the
             * "expr" subtree of the CaseWhen nodes.  But it doesn't really
             * seem worth any extra code.  If there are any bare CaseTestExprs
             * elsewhere in the CASE, something's wrong already.
             */
            *flags |= CCDN_CASETESTEXPR_OK;
            res = expression_tree_walker(node,
                                         contain_context_dependent_node_walker,
                                         flags);
            *flags = save_flags;
            return res;
        }
    }
    else if (IsA(node, ArrayCoerceExpr))
    {
        ArrayCoerceExpr *ac = (ArrayCoerceExpr *) node;
        int         save_flags;
        bool        res;
 
        /* Check the array expression */
        if (contain_context_dependent_node_walker((Node *) ac->arg, flags))
            return true;
 
        /* Check the elemexpr, which is allowed to contain CaseTestExpr */
        save_flags = *flags;
        *flags |= CCDN_CASETESTEXPR_OK;
        res = contain_context_dependent_node_walker((Node *) ac->elemexpr,
                                                    flags);
        *flags = save_flags;
        return res;
    }
    return expression_tree_walker(node, contain_context_dependent_node_walker,
                                  flags);
}

References ArrayCoerceExpr::arg, CaseExpr::arg, CCDN_CASETESTEXPR_OK, contain_context_dependent_node_walker(), ArrayCoerceExpr::elemexpr, expression_tree_walker, and IsA.

Referenced by contain_context_dependent_node(), and contain_context_dependent_node_walker().

contain_exec_param()

bool contain_exec_param	(	Node *	clause,
		List *	param_ids
	)

Definition at line 1143 of file clauses.c.

{
    return contain_exec_param_walker(clause, param_ids);
}

References contain_exec_param_walker().

Referenced by test_opexpr_is_hashable().

contain_exec_param_walker()

static bool contain_exec_param_walker ( Node *  node, List *  param_ids  )

static

Definition at line 1149 of file clauses.c.

{
    if (node == NULL)
        return false;
    if (IsA(node, Param))
    {
        Param      *p = (Param *) node;
 
        if (p->paramkind == PARAM_EXEC &&
            list_member_int(param_ids, p->paramid))
            return true;
    }
    return expression_tree_walker(node, contain_exec_param_walker, param_ids);
}

References contain_exec_param_walker(), expression_tree_walker, IsA, list_member_int(), PARAM_EXEC, Param::paramid, and Param::paramkind.

Referenced by contain_exec_param(), and contain_exec_param_walker().

contain_leaked_vars()

bool contain_leaked_vars

(

Node *

clause

)

Definition at line 1269 of file clauses.c.

{
    return contain_leaked_vars_walker(clause, NULL);
}

References contain_leaked_vars_walker().

Referenced by make_plain_restrictinfo(), and qual_is_pushdown_safe().

contain_leaked_vars_checker()

static bool contain_leaked_vars_checker ( Oid  func_id, void *  context  )

static

Definition at line 1275 of file clauses.c.

{
    return !get_func_leakproof(func_id);
}

References get_func_leakproof().

Referenced by contain_leaked_vars_walker().

contain_leaked_vars_walker()

static bool contain_leaked_vars_walker ( Node *  node, void *  context  )

static

Definition at line 1281 of file clauses.c.

{
    if (node == NULL)
        return false;
 
    switch (nodeTag(node))
    {
        case T_Var:
        case T_Const:
        case T_Param:
        case T_ArrayExpr:
        case T_FieldSelect:
        case T_FieldStore:
        case T_NamedArgExpr:
        case T_BoolExpr:
        case T_RelabelType:
        case T_CollateExpr:
        case T_CaseExpr:
        case T_CaseTestExpr:
        case T_RowExpr:
        case T_SQLValueFunction:
        case T_NullTest:
        case T_BooleanTest:
        case T_NextValueExpr:
        case T_ReturningExpr:
        case T_List:
 
            /*
             * We know these node types don't contain function calls; but
             * something further down in the node tree might.
             */
            break;
 
        case T_FuncExpr:
        case T_OpExpr:
        case T_DistinctExpr:
        case T_NullIfExpr:
        case T_ScalarArrayOpExpr:
        case T_CoerceViaIO:
        case T_ArrayCoerceExpr:
 
            /*
             * If node contains a leaky function call, and there's any Var
             * underneath it, reject.
             */
            if (check_functions_in_node(node, contain_leaked_vars_checker,
                                        context) &&
                contain_var_clause(node))
                return true;
            break;
 
        case T_SubscriptingRef:
            {
                SubscriptingRef *sbsref = (SubscriptingRef *) node;
                const SubscriptRoutines *sbsroutines;
 
                /* Consult the subscripting support method info */
                sbsroutines = getSubscriptingRoutines(sbsref->refcontainertype,
                                                      NULL);
                if (!sbsroutines ||
                    !(sbsref->refassgnexpr != NULL ?
                      sbsroutines->store_leakproof :
                      sbsroutines->fetch_leakproof))
                {
                    /* Node is leaky, so reject if it contains Vars */
                    if (contain_var_clause(node))
                        return true;
                }
            }
            break;
 
        case T_RowCompareExpr:
            {
                /*
                 * It's worth special-casing this because a leaky comparison
                 * function only compromises one pair of row elements, which
                 * might not contain Vars while others do.
                 */
                RowCompareExpr *rcexpr = (RowCompareExpr *) node;
                ListCell   *opid;
                ListCell   *larg;
                ListCell   *rarg;
 
                forthree(opid, rcexpr->opnos,
                         larg, rcexpr->largs,
                         rarg, rcexpr->rargs)
                {
                    Oid         funcid = get_opcode(lfirst_oid(opid));
 
                    if (!get_func_leakproof(funcid) &&
                        (contain_var_clause((Node *) lfirst(larg)) ||
                         contain_var_clause((Node *) lfirst(rarg))))
                        return true;
                }
            }
            break;
 
        case T_MinMaxExpr:
            {
                /*
                 * MinMaxExpr is leakproof if the comparison function it calls
                 * is leakproof.
                 */
                MinMaxExpr *minmaxexpr = (MinMaxExpr *) node;
                TypeCacheEntry *typentry;
                bool        leakproof;
 
                /* Look up the btree comparison function for the datatype */
                typentry = lookup_type_cache(minmaxexpr->minmaxtype,
                                             TYPECACHE_CMP_PROC);
                if (OidIsValid(typentry->cmp_proc))
                    leakproof = get_func_leakproof(typentry->cmp_proc);
                else
                {
                    /*
                     * The executor will throw an error, but here we just
                     * treat the missing function as leaky.
                     */
                    leakproof = false;
                }
 
                if (!leakproof &&
                    contain_var_clause((Node *) minmaxexpr->args))
                    return true;
            }
            break;
 
        case T_CurrentOfExpr:
 
            /*
             * WHERE CURRENT OF doesn't contain leaky function calls.
             * Moreover, it is essential that this is considered non-leaky,
             * since the planner must always generate a TID scan when CURRENT
             * OF is present -- cf. cost_tidscan.
             */
            return false;
 
        default:
 
            /*
             * If we don't recognize the node tag, assume it might be leaky.
             * This prevents an unexpected security hole if someone adds a new
             * node type that can call a function.
             */
            return true;
    }
    return expression_tree_walker(node, contain_leaked_vars_walker,
                                  context);
}

References MinMaxExpr::args, check_functions_in_node(), TypeCacheEntry::cmp_proc, contain_leaked_vars_checker(), contain_leaked_vars_walker(), contain_var_clause(), expression_tree_walker, SubscriptRoutines::fetch_leakproof, forthree, get_func_leakproof(), get_opcode(), getSubscriptingRoutines(), RowCompareExpr::largs, lfirst, lfirst_oid, lookup_type_cache(), nodeTag, OidIsValid, RowCompareExpr::rargs, SubscriptingRef::refassgnexpr, SubscriptRoutines::store_leakproof, and TYPECACHE_CMP_PROC.

Referenced by contain_leaked_vars(), and contain_leaked_vars_walker().

contain_mutable_functions()

bool contain_mutable_functions

(

Node *

clause

)

Definition at line 374 of file clauses.c.

{
    return contain_mutable_functions_walker(clause, NULL);
}

References contain_mutable_functions_walker().

Referenced by can_minmax_aggs(), check_index_predicates(), ComputePartitionAttrs(), contain_mutable_functions_after_planning(), create_bitmap_scan_plan(), create_indexscan_plan(), eval_const_expressions_mutator(), exec_save_simple_expr(), inline_function(), is_foreign_expr(), and relation_excluded_by_constraints().

contain_mutable_functions_after_planning()

bool contain_mutable_functions_after_planning

(

Expr *

expr

)

Definition at line 494 of file clauses.c.

{
    /* We assume here that expression_planner() won't scribble on its input */
    expr = expression_planner(expr);
 
    /* Now we can search for non-immutable functions */
    return contain_mutable_functions((Node *) expr);
}

References contain_mutable_functions(), and expression_planner().

Referenced by CheckPredicate(), ComputeIndexAttrs(), and cookDefault().

contain_mutable_functions_checker()

static bool contain_mutable_functions_checker ( Oid  func_id, void *  context  )

static

Definition at line 380 of file clauses.c.

{
    return (func_volatile(func_id) != PROVOLATILE_IMMUTABLE);
}

References func_volatile().

Referenced by contain_mutable_functions_walker().

contain_mutable_functions_walker()

static bool contain_mutable_functions_walker ( Node *  node, void *  context  )

static

Definition at line 386 of file clauses.c.

{
    if (node == NULL)
        return false;
    /* Check for mutable functions in node itself */
    if (check_functions_in_node(node, contain_mutable_functions_checker,
                                context))
        return true;
 
    if (IsA(node, JsonConstructorExpr))
    {
        const JsonConstructorExpr *ctor = (JsonConstructorExpr *) node;
        ListCell   *lc;
        bool        is_jsonb;
 
        is_jsonb = ctor->returning->format->format_type == JS_FORMAT_JSONB;
 
        /*
         * Check argument_type => json[b] conversions specifically.  We still
         * recurse to check 'args' below, but here we want to specifically
         * check whether or not the emitted clause would fail to be immutable
         * because of TimeZone, for example.
         */
        foreach(lc, ctor->args)
        {
            Oid         typid = exprType(lfirst(lc));
 
            if (is_jsonb ?
                !to_jsonb_is_immutable(typid) :
                !to_json_is_immutable(typid))
                return true;
        }
 
        /* Check all subnodes */
    }
 
    if (IsA(node, JsonExpr))
    {
        JsonExpr   *jexpr = castNode(JsonExpr, node);
        Const      *cnst;
 
        if (!IsA(jexpr->path_spec, Const))
            return true;
 
        cnst = castNode(Const, jexpr->path_spec);
 
        Assert(cnst->consttype == JSONPATHOID);
        if (cnst->constisnull)
            return false;
 
        if (jspIsMutable(DatumGetJsonPathP(cnst->constvalue),
                         jexpr->passing_names, jexpr->passing_values))
            return true;
    }
 
    if (IsA(node, SQLValueFunction))
    {
        /* all variants of SQLValueFunction are stable */
        return true;
    }
 
    if (IsA(node, NextValueExpr))
    {
        /* NextValueExpr is volatile */
        return true;
    }
 
    /*
     * It should be safe to treat MinMaxExpr as immutable, because it will
     * depend on a non-cross-type btree comparison function, and those should
     * always be immutable.  Treating XmlExpr as immutable is more dubious,
     * and treating CoerceToDomain as immutable is outright dangerous.  But we
     * have done so historically, and changing this would probably cause more
     * problems than it would fix.  In practice, if you have a non-immutable
     * domain constraint you are in for pain anyhow.
     */
 
    /* Recurse to check arguments */
    if (IsA(node, Query))
    {
        /* Recurse into subselects */
        return query_tree_walker((Query *) node,
                                 contain_mutable_functions_walker,
                                 context, 0);
    }
    return expression_tree_walker(node, contain_mutable_functions_walker,
                                  context);
}

References JsonConstructorExpr::args, Assert(), castNode, check_functions_in_node(), Const::consttype, contain_mutable_functions_checker(), contain_mutable_functions_walker(), DatumGetJsonPathP(), expression_tree_walker, exprType(), JsonReturning::format, JsonFormat::format_type, IsA, JS_FORMAT_JSONB, jspIsMutable(), lfirst, JsonExpr::passing_names, JsonExpr::passing_values, JsonExpr::path_spec, query_tree_walker, JsonConstructorExpr::returning, to_json_is_immutable(), and to_jsonb_is_immutable().

Referenced by contain_mutable_functions(), and contain_mutable_functions_walker().

contain_non_const_walker()

static bool contain_non_const_walker ( Node *  node, void *  context  )

static

Definition at line 3779 of file clauses.c.

{
    if (node == NULL)
        return false;
    if (IsA(node, Const))
        return false;
    if (IsA(node, List))
        return expression_tree_walker(node, contain_non_const_walker, context);
    /* Otherwise, abort the tree traversal and return true */
    return true;
}

References contain_non_const_walker(), expression_tree_walker, and IsA.

Referenced by contain_non_const_walker().

contain_nonstrict_functions()

bool contain_nonstrict_functions

(

Node *

clause

)

Definition at line 997 of file clauses.c.

{
    return contain_nonstrict_functions_walker(clause, NULL);
}

References contain_nonstrict_functions_walker().

Referenced by inline_function(), and pullup_replace_vars_callback().

contain_nonstrict_functions_checker()

static bool contain_nonstrict_functions_checker ( Oid  func_id, void *  context  )

static

Definition at line 1003 of file clauses.c.

{
    return !func_strict(func_id);
}

References func_strict().

Referenced by contain_nonstrict_functions_walker().

contain_nonstrict_functions_walker()

static bool contain_nonstrict_functions_walker ( Node *  node, void *  context  )

static

Definition at line 1009 of file clauses.c.

{
    if (node == NULL)
        return false;
    if (IsA(node, Aggref))
    {
        /* an aggregate could return non-null with null input */
        return true;
    }
    if (IsA(node, GroupingFunc))
    {
        /*
         * A GroupingFunc doesn't evaluate its arguments, and therefore must
         * be treated as nonstrict.
         */
        return true;
    }
    if (IsA(node, WindowFunc))
    {
        /* a window function could return non-null with null input */
        return true;
    }
    if (IsA(node, SubscriptingRef))
    {
        SubscriptingRef *sbsref = (SubscriptingRef *) node;
        const SubscriptRoutines *sbsroutines;
 
        /* Subscripting assignment is always presumed nonstrict */
        if (sbsref->refassgnexpr != NULL)
            return true;
        /* Otherwise we must look up the subscripting support methods */
        sbsroutines = getSubscriptingRoutines(sbsref->refcontainertype, NULL);
        if (!(sbsroutines && sbsroutines->fetch_strict))
            return true;
        /* else fall through to check args */
    }
    if (IsA(node, DistinctExpr))
    {
        /* IS DISTINCT FROM is inherently non-strict */
        return true;
    }
    if (IsA(node, NullIfExpr))
    {
        /* NULLIF is inherently non-strict */
        return true;
    }
    if (IsA(node, BoolExpr))
    {
        BoolExpr   *expr = (BoolExpr *) node;
 
        switch (expr->boolop)
        {
            case AND_EXPR:
            case OR_EXPR:
                /* AND, OR are inherently non-strict */
                return true;
            default:
                break;
        }
    }
    if (IsA(node, SubLink))
    {
        /* In some cases a sublink might be strict, but in general not */
        return true;
    }
    if (IsA(node, SubPlan))
        return true;
    if (IsA(node, AlternativeSubPlan))
        return true;
    if (IsA(node, FieldStore))
        return true;
    if (IsA(node, CoerceViaIO))
    {
        /*
         * CoerceViaIO is strict regardless of whether the I/O functions are,
         * so just go look at its argument; asking check_functions_in_node is
         * useless expense and could deliver the wrong answer.
         */
        return contain_nonstrict_functions_walker((Node *) ((CoerceViaIO *) node)->arg,
                                                  context);
    }
    if (IsA(node, ArrayCoerceExpr))
    {
        /*
         * ArrayCoerceExpr is strict at the array level, regardless of what
         * the per-element expression is; so we should ignore elemexpr and
         * recurse only into the arg.
         */
        return contain_nonstrict_functions_walker((Node *) ((ArrayCoerceExpr *) node)->arg,
                                                  context);
    }
    if (IsA(node, CaseExpr))
        return true;
    if (IsA(node, ArrayExpr))
        return true;
    if (IsA(node, RowExpr))
        return true;
    if (IsA(node, RowCompareExpr))
        return true;
    if (IsA(node, CoalesceExpr))
        return true;
    if (IsA(node, MinMaxExpr))
        return true;
    if (IsA(node, XmlExpr))
        return true;
    if (IsA(node, NullTest))
        return true;
    if (IsA(node, BooleanTest))
        return true;
    if (IsA(node, JsonConstructorExpr))
        return true;
 
    /* Check other function-containing nodes */
    if (check_functions_in_node(node, contain_nonstrict_functions_checker,
                                context))
        return true;
 
    return expression_tree_walker(node, contain_nonstrict_functions_walker,
                                  context);
}

References AND_EXPR, arg, BoolExpr::boolop, check_functions_in_node(), contain_nonstrict_functions_checker(), contain_nonstrict_functions_walker(), expression_tree_walker, SubscriptRoutines::fetch_strict, getSubscriptingRoutines(), IsA, OR_EXPR, and SubscriptingRef::refassgnexpr.

Referenced by contain_nonstrict_functions(), and contain_nonstrict_functions_walker().

contain_subplans()

bool contain_subplans

(

Node *

clause

)

Definition at line 334 of file clauses.c.

{
    return contain_subplans_walker(clause, NULL);
}

References contain_subplans_walker().

Referenced by convert_EXISTS_to_ANY(), ExecInitValuesScan(), find_simplified_clause(), find_window_run_conditions(), initialize_peragg(), inline_function(), inline_set_returning_function(), qual_is_pushdown_safe(), and subquery_planner().

contain_subplans_walker()

static bool contain_subplans_walker ( Node *  node, void *  context  )

static

Definition at line 340 of file clauses.c.

{
    if (node == NULL)
        return false;
    if (IsA(node, SubPlan) ||
        IsA(node, AlternativeSubPlan) ||
        IsA(node, SubLink))
        return true;            /* abort the tree traversal and return true */
    return expression_tree_walker(node, contain_subplans_walker, context);
}

References contain_subplans_walker(), expression_tree_walker, and IsA.

Referenced by contain_subplans(), and contain_subplans_walker().

contain_volatile_functions()

bool contain_volatile_functions

(

Node *

clause

)

Definition at line 542 of file clauses.c.

{
    return contain_volatile_functions_walker(clause, NULL);
}

References contain_volatile_functions_walker().

Referenced by apply_child_basequals(), ATExecAddColumn(), check_hashjoinable(), check_mergejoinable(), check_output_expressions(), compute_semijoin_info(), contain_volatile_functions_after_planning(), convert_ANY_sublink_to_join(), convert_EXISTS_sublink_to_join(), convert_EXISTS_to_ANY(), convert_VALUES_to_ANY(), CopyFrom(), distribute_qual_to_rels(), estimate_num_groups(), ExecInitWindowAgg(), expand_indexqual_rowcompare(), find_compatible_agg(), find_simplified_clause(), get_eclass_for_sort_expr(), get_memoize_path(), group_similar_or_args(), initialize_peragg(), inline_function(), inline_set_returning_function(), is_pseudo_constant_clause(), is_pseudo_constant_clause_relids(), is_pseudo_constant_for_index(), is_safe_restriction_clause_for(), is_simple_subquery(), is_simple_values(), IsBinaryTidClause(), IsTidEqualAnyClause(), make_sort_input_target(), mark_nullable_by_grouping(), match_clause_to_ordering_op(), match_clause_to_partition_key(), match_opclause_to_indexcol(), match_orclause_to_indexcol(), match_rowcompare_to_indexcol(), match_saopclause_to_indexcol(), paraminfo_get_equal_hashops(), qual_is_pushdown_safe(), remove_unused_subquery_outputs(), SS_process_ctes(), and subquery_planner().

contain_volatile_functions_after_planning()

bool contain_volatile_functions_after_planning

(

Expr *

expr

)

Definition at line 663 of file clauses.c.

{
    /* We assume here that expression_planner() won't scribble on its input */
    expr = expression_planner(expr);
 
    /* Now we can search for volatile functions */
    return contain_volatile_functions((Node *) expr);
}

References contain_volatile_functions(), and expression_planner().

contain_volatile_functions_checker()

static bool contain_volatile_functions_checker ( Oid  func_id, void *  context  )

static

Definition at line 548 of file clauses.c.

{
    return (func_volatile(func_id) == PROVOLATILE_VOLATILE);
}

References func_volatile().

Referenced by contain_volatile_functions_walker().

contain_volatile_functions_not_nextval()

bool contain_volatile_functions_not_nextval

(

Node *

clause

)

Definition at line 677 of file clauses.c.

{
    return contain_volatile_functions_not_nextval_walker(clause, NULL);
}

References contain_volatile_functions_not_nextval_walker().

Referenced by BeginCopyFrom().

contain_volatile_functions_not_nextval_checker()

static bool contain_volatile_functions_not_nextval_checker ( Oid  func_id, void *  context  )

static

Definition at line 683 of file clauses.c.

{
    return (func_id != F_NEXTVAL &&
            func_volatile(func_id) == PROVOLATILE_VOLATILE);
}

References func_volatile().

Referenced by contain_volatile_functions_not_nextval_walker().

contain_volatile_functions_not_nextval_walker()

static bool contain_volatile_functions_not_nextval_walker ( Node *  node, void *  context  )

static

Definition at line 690 of file clauses.c.

{
    if (node == NULL)
        return false;
    /* Check for volatile functions in node itself */
    if (check_functions_in_node(node,
                                contain_volatile_functions_not_nextval_checker,
                                context))
        return true;
 
    /*
     * See notes in contain_mutable_functions_walker about why we treat
     * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
     * SQLValueFunction is stable.  Hence, none of them are of interest here.
     * Also, since we're intentionally ignoring nextval(), presumably we
     * should ignore NextValueExpr.
     */
 
    /* Recurse to check arguments */
    if (IsA(node, Query))
    {
        /* Recurse into subselects */
        return query_tree_walker((Query *) node,
                                 contain_volatile_functions_not_nextval_walker,
                                 context, 0);
    }
    return expression_tree_walker(node,
                                  contain_volatile_functions_not_nextval_walker,
                                  context);
}

References check_functions_in_node(), contain_volatile_functions_not_nextval_checker(), contain_volatile_functions_not_nextval_walker(), expression_tree_walker, IsA, and query_tree_walker.

Referenced by contain_volatile_functions_not_nextval(), and contain_volatile_functions_not_nextval_walker().

contain_volatile_functions_walker()

static bool contain_volatile_functions_walker ( Node *  node, void *  context  )

static

Definition at line 554 of file clauses.c.

{
    if (node == NULL)
        return false;
    /* Check for volatile functions in node itself */
    if (check_functions_in_node(node, contain_volatile_functions_checker,
                                context))
        return true;
 
    if (IsA(node, NextValueExpr))
    {
        /* NextValueExpr is volatile */
        return true;
    }
 
    if (IsA(node, RestrictInfo))
    {
        RestrictInfo *rinfo = (RestrictInfo *) node;
 
        /*
         * For RestrictInfo, check if we've checked the volatility of it
         * before.  If so, we can just use the cached value and not bother
         * checking it again.  Otherwise, check it and cache if whether we
         * found any volatile functions.
         */
        if (rinfo->has_volatile == VOLATILITY_NOVOLATILE)
            return false;
        else if (rinfo->has_volatile == VOLATILITY_VOLATILE)
            return true;
        else
        {
            bool        hasvolatile;
 
            hasvolatile = contain_volatile_functions_walker((Node *) rinfo->clause,
                                                            context);
            if (hasvolatile)
                rinfo->has_volatile = VOLATILITY_VOLATILE;
            else
                rinfo->has_volatile = VOLATILITY_NOVOLATILE;
 
            return hasvolatile;
        }
    }
 
    if (IsA(node, PathTarget))
    {
        PathTarget *target = (PathTarget *) node;
 
        /*
         * We also do caching for PathTarget the same as we do above for
         * RestrictInfos.
         */
        if (target->has_volatile_expr == VOLATILITY_NOVOLATILE)
            return false;
        else if (target->has_volatile_expr == VOLATILITY_VOLATILE)
            return true;
        else
        {
            bool        hasvolatile;
 
            hasvolatile = contain_volatile_functions_walker((Node *) target->exprs,
                                                            context);
 
            if (hasvolatile)
                target->has_volatile_expr = VOLATILITY_VOLATILE;
            else
                target->has_volatile_expr = VOLATILITY_NOVOLATILE;
 
            return hasvolatile;
        }
    }
 
    /*
     * See notes in contain_mutable_functions_walker about why we treat
     * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
     * SQLValueFunction is stable.  Hence, none of them are of interest here.
     */
 
    /* Recurse to check arguments */
    if (IsA(node, Query))
    {
        /* Recurse into subselects */
        return query_tree_walker((Query *) node,
                                 contain_volatile_functions_walker,
                                 context, 0);
    }
    return expression_tree_walker(node, contain_volatile_functions_walker,
                                  context);
}

References check_functions_in_node(), RestrictInfo::clause, contain_volatile_functions_checker(), contain_volatile_functions_walker(), expression_tree_walker, PathTarget::exprs, PathTarget::has_volatile_expr, IsA, query_tree_walker, VOLATILITY_NOVOLATILE, and VOLATILITY_VOLATILE.

Referenced by contain_volatile_functions(), and contain_volatile_functions_walker().

contain_window_function()

bool contain_window_function

(

Node *

clause

)

Definition at line 219 of file clauses.c.

{
    return contain_windowfuncs(clause);
}

References contain_windowfuncs().

Referenced by get_eclass_for_sort_expr(), and mark_nullable_by_grouping().

convert_saop_to_hashed_saop()

void convert_saop_to_hashed_saop

(

Node *

node

)

Definition at line 2295 of file clauses.c.

{
    (void) convert_saop_to_hashed_saop_walker(node, NULL);
}

References convert_saop_to_hashed_saop_walker().

Referenced by preprocess_expression().

convert_saop_to_hashed_saop_walker()

static bool convert_saop_to_hashed_saop_walker ( Node *  node, void *  context  )

static

Definition at line 2301 of file clauses.c.

{
    if (node == NULL)
        return false;
 
    if (IsA(node, ScalarArrayOpExpr))
    {
        ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) node;
        Expr       *arrayarg = (Expr *) lsecond(saop->args);
        Oid         lefthashfunc;
        Oid         righthashfunc;
 
        if (arrayarg && IsA(arrayarg, Const) &&
            !((Const *) arrayarg)->constisnull)
        {
            if (saop->useOr)
            {
                if (get_op_hash_functions(saop->opno, &lefthashfunc, &righthashfunc) &&
                    lefthashfunc == righthashfunc)
                {
                    Datum       arrdatum = ((Const *) arrayarg)->constvalue;
                    ArrayType  *arr = (ArrayType *) DatumGetPointer(arrdatum);
                    int         nitems;
 
                    /*
                     * Only fill in the hash functions if the array looks
                     * large enough for it to be worth hashing instead of
                     * doing a linear search.
                     */
                    nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
 
                    if (nitems >= MIN_ARRAY_SIZE_FOR_HASHED_SAOP)
                    {
                        /* Looks good. Fill in the hash functions */
                        saop->hashfuncid = lefthashfunc;
                    }
                    return false;
                }
            }
            else                /* !saop->useOr */
            {
                Oid         negator = get_negator(saop->opno);
 
                /*
                 * Check if this is a NOT IN using an operator whose negator
                 * is hashable.  If so we can still build a hash table and
                 * just ensure the lookup items are not in the hash table.
                 */
                if (OidIsValid(negator) &&
                    get_op_hash_functions(negator, &lefthashfunc, &righthashfunc) &&
                    lefthashfunc == righthashfunc)
                {
                    Datum       arrdatum = ((Const *) arrayarg)->constvalue;
                    ArrayType  *arr = (ArrayType *) DatumGetPointer(arrdatum);
                    int         nitems;
 
                    /*
                     * Only fill in the hash functions if the array looks
                     * large enough for it to be worth hashing instead of
                     * doing a linear search.
                     */
                    nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
 
                    if (nitems >= MIN_ARRAY_SIZE_FOR_HASHED_SAOP)
                    {
                        /* Looks good. Fill in the hash functions */
                        saop->hashfuncid = lefthashfunc;
 
                        /*
                         * Also set the negfuncid.  The executor will need
                         * that to perform hashtable lookups.
                         */
                        saop->negfuncid = get_opcode(negator);
                    }
                    return false;
                }
            }
        }
    }
 
    return expression_tree_walker(node, convert_saop_to_hashed_saop_walker, NULL);
}

References ScalarArrayOpExpr::args, ARR_DIMS, ARR_NDIM, ArrayGetNItems(), convert_saop_to_hashed_saop_walker(), DatumGetPointer(), expression_tree_walker, get_negator(), get_op_hash_functions(), get_opcode(), IsA, lsecond, MIN_ARRAY_SIZE_FOR_HASHED_SAOP, nitems, OidIsValid, ScalarArrayOpExpr::opno, and ScalarArrayOpExpr::useOr.

Referenced by convert_saop_to_hashed_saop(), and convert_saop_to_hashed_saop_walker().

ece_function_is_safe()

static bool ece_function_is_safe ( Oid  funcid, eval_const_expressions_context *  context  )

static

Definition at line 3795 of file clauses.c.

{
    char        provolatile = func_volatile(funcid);
 
    /*
     * Ordinarily we are only allowed to simplify immutable functions. But for
     * purposes of estimation, we consider it okay to simplify functions that
     * are merely stable; the risk that the result might change from planning
     * time to execution time is worth taking in preference to not being able
     * to estimate the value at all.
     */
    if (provolatile == PROVOLATILE_IMMUTABLE)
        return true;
    if (context->estimate && provolatile == PROVOLATILE_STABLE)
        return true;
    return false;
}

References eval_const_expressions_context::estimate, and func_volatile().

Referenced by eval_const_expressions_mutator().

estimate_expression_value()

Node * estimate_expression_value	(	PlannerInfo *	root,
		Node *	node
	)

Definition at line 2403 of file clauses.c.

{
    eval_const_expressions_context context;
 
    context.boundParams = root->glob->boundParams;  /* bound Params */
    /* we do not need to mark the plan as depending on inlined functions */
    context.root = NULL;
    context.active_fns = NIL;   /* nothing being recursively simplified */
    context.case_val = NULL;    /* no CASE being examined */
    context.estimate = true;    /* unsafe transformations OK */
    return eval_const_expressions_mutator(node, &context);
}

References eval_const_expressions_context::active_fns, eval_const_expressions_context::boundParams, eval_const_expressions_context::case_val, eval_const_expressions_context::estimate, eval_const_expressions_mutator(), NIL, eval_const_expressions_context::root, and root.

Referenced by array_unnest_support(), bernoulli_samplescangetsamplesize(), clause_selectivity_ext(), generate_series_int4_support(), generate_series_int8_support(), generate_series_numeric_support(), generate_series_timestamp_support(), get_restriction_variable(), gincost_opexpr(), gincost_scalararrayopexpr(), preprocess_limit(), scalararraysel(), system_rows_samplescangetsamplesize(), system_samplescangetsamplesize(), and system_time_samplescangetsamplesize().

eval_const_expressions()

Node * eval_const_expressions	(	PlannerInfo *	root,
		Node *	node
	)

Definition at line 2262 of file clauses.c.

{
    eval_const_expressions_context context;
 
    if (root)
        context.boundParams = root->glob->boundParams;  /* bound Params */
    else
        context.boundParams = NULL;
    context.root = root;        /* for inlined-function dependencies */
    context.active_fns = NIL;   /* nothing being recursively simplified */
    context.case_val = NULL;    /* no CASE being examined */
    context.estimate = false;   /* safe transformations only */
    return eval_const_expressions_mutator(node, &context);
}

References eval_const_expressions_context::active_fns, eval_const_expressions_context::boundParams, eval_const_expressions_context::case_val, eval_const_expressions_context::estimate, eval_const_expressions_mutator(), NIL, eval_const_expressions_context::root, and root.

Referenced by apply_child_basequals(), ATExecAttachPartition(), ConstraintImpliedByRelConstraint(), convert_EXISTS_to_ANY(), convert_VALUES_to_ANY(), DetachAddConstraintIfNeeded(), DoCopy(), expand_insert_targetlist(), expression_planner(), expression_planner_with_deps(), fetch_statentries_for_relation(), get_proposed_default_constraint(), get_relation_constraints(), get_relation_statistics(), preprocess_expression(), preprocess_function_rtes(), process_implied_equality(), RelationBuildPartitionKey(), RelationGetIndexExpressions(), RelationGetIndexPredicate(), and simplify_EXISTS_query().

eval_const_expressions_mutator()

static Node * eval_const_expressions_mutator ( Node *  node, eval_const_expressions_context *  context  )

static

Definition at line 2448 of file clauses.c.

{
 
    /* since this function recurses, it could be driven to stack overflow */
    check_stack_depth();
 
    if (node == NULL)
        return NULL;
    switch (nodeTag(node))
    {
        case T_Param:
            {
                Param      *param = (Param *) node;
                ParamListInfo paramLI = context->boundParams;
 
                /* Look to see if we've been given a value for this Param */
                if (param->paramkind == PARAM_EXTERN &&
                    paramLI != NULL &&
                    param->paramid > 0 &&
                    param->paramid <= paramLI->numParams)
                {
                    ParamExternData *prm;
                    ParamExternData prmdata;
 
                    /*
                     * Give hook a chance in case parameter is dynamic.  Tell
                     * it that this fetch is speculative, so it should avoid
                     * erroring out if parameter is unavailable.
                     */
                    if (paramLI->paramFetch != NULL)
                        prm = paramLI->paramFetch(paramLI, param->paramid,
                                                  true, &prmdata);
                    else
                        prm = &paramLI->params[param->paramid - 1];
 
                    /*
                     * We don't just check OidIsValid, but insist that the
                     * fetched type match the Param, just in case the hook did
                     * something unexpected.  No need to throw an error here
                     * though; leave that for runtime.
                     */
                    if (OidIsValid(prm->ptype) &&
                        prm->ptype == param->paramtype)
                    {
                        /* OK to substitute parameter value? */
                        if (context->estimate ||
                            (prm->pflags & PARAM_FLAG_CONST))
                        {
                            /*
                             * Return a Const representing the param value.
                             * Must copy pass-by-ref datatypes, since the
                             * Param might be in a memory context
                             * shorter-lived than our output plan should be.
                             */
                            int16       typLen;
                            bool        typByVal;
                            Datum       pval;
                            Const      *con;
 
                            get_typlenbyval(param->paramtype,
                                            &typLen, &typByVal);
                            if (prm->isnull || typByVal)
                                pval = prm->value;
                            else
                                pval = datumCopy(prm->value, typByVal, typLen);
                            con = makeConst(param->paramtype,
                                            param->paramtypmod,
                                            param->paramcollid,
                                            (int) typLen,
                                            pval,
                                            prm->isnull,
                                            typByVal);
                            con->location = param->location;
                            return (Node *) con;
                        }
                    }
                }
 
                /*
                 * Not replaceable, so just copy the Param (no need to
                 * recurse)
                 */
                return (Node *) copyObject(param);
            }
        case T_WindowFunc:
            {
                WindowFunc *expr = (WindowFunc *) node;
                Oid         funcid = expr->winfnoid;
                List       *args;
                Expr       *aggfilter;
                HeapTuple   func_tuple;
                WindowFunc *newexpr;
 
                /*
                 * We can't really simplify a WindowFunc node, but we mustn't
                 * just fall through to the default processing, because we
                 * have to apply expand_function_arguments to its argument
                 * list.  That takes care of inserting default arguments and
                 * expanding named-argument notation.
                 */
                func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
                if (!HeapTupleIsValid(func_tuple))
                    elog(ERROR, "cache lookup failed for function %u", funcid);
 
                args = expand_function_arguments(expr->args,
                                                 false, expr->wintype,
                                                 func_tuple);
 
                ReleaseSysCache(func_tuple);
 
                /* Now, recursively simplify the args (which are a List) */
                args = (List *)
                    expression_tree_mutator((Node *) args,
                                            eval_const_expressions_mutator,
                                            context);
                /* ... and the filter expression, which isn't */
                aggfilter = (Expr *)
                    eval_const_expressions_mutator((Node *) expr->aggfilter,
                                                   context);
 
                /* And build the replacement WindowFunc node */
                newexpr = makeNode(WindowFunc);
                newexpr->winfnoid = expr->winfnoid;
                newexpr->wintype = expr->wintype;
                newexpr->wincollid = expr->wincollid;
                newexpr->inputcollid = expr->inputcollid;
                newexpr->args = args;
                newexpr->aggfilter = aggfilter;
                newexpr->runCondition = expr->runCondition;
                newexpr->winref = expr->winref;
                newexpr->winstar = expr->winstar;
                newexpr->winagg = expr->winagg;
                newexpr->ignore_nulls = expr->ignore_nulls;
                newexpr->location = expr->location;
 
                return (Node *) newexpr;
            }
        case T_FuncExpr:
            {
                FuncExpr   *expr = (FuncExpr *) node;
                List       *args = expr->args;
                Expr       *simple;
                FuncExpr   *newexpr;
 
                /*
                 * Code for op/func reduction is pretty bulky, so split it out
                 * as a separate function.  Note: exprTypmod normally returns
                 * -1 for a FuncExpr, but not when the node is recognizably a
                 * length coercion; we want to preserve the typmod in the
                 * eventual Const if so.
                 */
                simple = simplify_function(expr->funcid,
                                           expr->funcresulttype,
                                           exprTypmod(node),
                                           expr->funccollid,
                                           expr->inputcollid,
                                           &args,
                                           expr->funcvariadic,
                                           true,
                                           true,
                                           context);
                if (simple)     /* successfully simplified it */
                    return (Node *) simple;
 
                /*
                 * The expression cannot be simplified any further, so build
                 * and return a replacement FuncExpr node using the
                 * possibly-simplified arguments.  Note that we have also
                 * converted the argument list to positional notation.
                 */
                newexpr = makeNode(FuncExpr);
                newexpr->funcid = expr->funcid;
                newexpr->funcresulttype = expr->funcresulttype;
                newexpr->funcretset = expr->funcretset;
                newexpr->funcvariadic = expr->funcvariadic;
                newexpr->funcformat = expr->funcformat;
                newexpr->funccollid = expr->funccollid;
                newexpr->inputcollid = expr->inputcollid;
                newexpr->args = args;
                newexpr->location = expr->location;
                return (Node *) newexpr;
            }
        case T_OpExpr:
            {
                OpExpr     *expr = (OpExpr *) node;
                List       *args = expr->args;
                Expr       *simple;
                OpExpr     *newexpr;
 
                /*
                 * Need to get OID of underlying function.  Okay to scribble
                 * on input to this extent.
                 */
                set_opfuncid(expr);
 
                /*
                 * Code for op/func reduction is pretty bulky, so split it out
                 * as a separate function.
                 */
                simple = simplify_function(expr->opfuncid,
                                           expr->opresulttype, -1,
                                           expr->opcollid,
                                           expr->inputcollid,
                                           &args,
                                           false,
                                           true,
                                           true,
                                           context);
                if (simple)     /* successfully simplified it */
                    return (Node *) simple;
 
                /*
                 * If the operator is boolean equality or inequality, we know
                 * how to simplify cases involving one constant and one
                 * non-constant argument.
                 */
                if (expr->opno == BooleanEqualOperator ||
                    expr->opno == BooleanNotEqualOperator)
                {
                    simple = (Expr *) simplify_boolean_equality(expr->opno,
                                                                args);
                    if (simple) /* successfully simplified it */
                        return (Node *) simple;
                }
 
                /*
                 * The expression cannot be simplified any further, so build
                 * and return a replacement OpExpr node using the
                 * possibly-simplified arguments.
                 */
                newexpr = makeNode(OpExpr);
                newexpr->opno = expr->opno;
                newexpr->opfuncid = expr->opfuncid;
                newexpr->opresulttype = expr->opresulttype;
                newexpr->opretset = expr->opretset;
                newexpr->opcollid = expr->opcollid;
                newexpr->inputcollid = expr->inputcollid;
                newexpr->args = args;
                newexpr->location = expr->location;
                return (Node *) newexpr;
            }
        case T_DistinctExpr:
            {
                DistinctExpr *expr = (DistinctExpr *) node;
                List       *args;
                ListCell   *arg;
                bool        has_null_input = false;
                bool        all_null_input = true;
                bool        has_nonconst_input = false;
                Expr       *simple;
                DistinctExpr *newexpr;
 
                /*
                 * Reduce constants in the DistinctExpr's arguments.  We know
                 * args is either NIL or a List node, so we can call
                 * expression_tree_mutator directly rather than recursing to
                 * self.
                 */
                args = (List *) expression_tree_mutator((Node *) expr->args,
                                                        eval_const_expressions_mutator,
                                                        context);
 
                /*
                 * We must do our own check for NULLs because DistinctExpr has
                 * different results for NULL input than the underlying
                 * operator does.
                 */
                foreach(arg, args)
                {
                    if (IsA(lfirst(arg), Const))
                    {
                        has_null_input |= ((Const *) lfirst(arg))->constisnull;
                        all_null_input &= ((Const *) lfirst(arg))->constisnull;
                    }
                    else
                        has_nonconst_input = true;
                }
 
                /* all constants? then can optimize this out */
                if (!has_nonconst_input)
                {
                    /* all nulls? then not distinct */
                    if (all_null_input)
                        return makeBoolConst(false, false);
 
                    /* one null? then distinct */
                    if (has_null_input)
                        return makeBoolConst(true, false);
 
                    /* otherwise try to evaluate the '=' operator */
                    /* (NOT okay to try to inline it, though!) */
 
                    /*
                     * Need to get OID of underlying function.  Okay to
                     * scribble on input to this extent.
                     */
                    set_opfuncid((OpExpr *) expr);  /* rely on struct
                                                     * equivalence */
 
                    /*
                     * Code for op/func reduction is pretty bulky, so split it
                     * out as a separate function.
                     */
                    simple = simplify_function(expr->opfuncid,
                                               expr->opresulttype, -1,
                                               expr->opcollid,
                                               expr->inputcollid,
                                               &args,
                                               false,
                                               false,
                                               false,
                                               context);
                    if (simple) /* successfully simplified it */
                    {
                        /*
                         * Since the underlying operator is "=", must negate
                         * its result
                         */
                        Const      *csimple = castNode(Const, simple);
 
                        csimple->constvalue =
                            BoolGetDatum(!DatumGetBool(csimple->constvalue));
                        return (Node *) csimple;
                    }
                }
 
                /*
                 * The expression cannot be simplified any further, so build
                 * and return a replacement DistinctExpr node using the
                 * possibly-simplified arguments.
                 */
                newexpr = makeNode(DistinctExpr);
                newexpr->opno = expr->opno;
                newexpr->opfuncid = expr->opfuncid;
                newexpr->opresulttype = expr->opresulttype;
                newexpr->opretset = expr->opretset;
                newexpr->opcollid = expr->opcollid;
                newexpr->inputcollid = expr->inputcollid;
                newexpr->args = args;
                newexpr->location = expr->location;
                return (Node *) newexpr;
            }
        case T_NullIfExpr:
            {
                NullIfExpr *expr;
                ListCell   *arg;
                bool        has_nonconst_input = false;
 
                /* Copy the node and const-simplify its arguments */
                expr = (NullIfExpr *) ece_generic_processing(node);
 
                /* If either argument is NULL they can't be equal */
                foreach(arg, expr->args)
                {
                    if (!IsA(lfirst(arg), Const))
                        has_nonconst_input = true;
                    else if (((Const *) lfirst(arg))->constisnull)
                        return (Node *) linitial(expr->args);
                }
 
                /*
                 * Need to get OID of underlying function before checking if
                 * the function is OK to evaluate.
                 */
                set_opfuncid((OpExpr *) expr);
 
                if (!has_nonconst_input &&
                    ece_function_is_safe(expr->opfuncid, context))
                    return ece_evaluate_expr(expr);
 
                return (Node *) expr;
            }
        case T_ScalarArrayOpExpr:
            {
                ScalarArrayOpExpr *saop;
 
                /* Copy the node and const-simplify its arguments */
                saop = (ScalarArrayOpExpr *) ece_generic_processing(node);
 
                /* Make sure we know underlying function */
                set_sa_opfuncid(saop);
 
                /*
                 * If all arguments are Consts, and it's a safe function, we
                 * can fold to a constant
                 */
                if (ece_all_arguments_const(saop) &&
                    ece_function_is_safe(saop->opfuncid, context))
                    return ece_evaluate_expr(saop);
                return (Node *) saop;
            }
        case T_BoolExpr:
            {
                BoolExpr   *expr = (BoolExpr *) node;
 
                switch (expr->boolop)
                {
                    case OR_EXPR:
                        {
                            List       *newargs;
                            bool        haveNull = false;
                            bool        forceTrue = false;
 
                            newargs = simplify_or_arguments(expr->args,
                                                            context,
                                                            &haveNull,
                                                            &forceTrue);
                            if (forceTrue)
                                return makeBoolConst(true, false);
                            if (haveNull)
                                newargs = lappend(newargs,
                                                  makeBoolConst(false, true));
                            /* If all the inputs are FALSE, result is FALSE */
                            if (newargs == NIL)
                                return makeBoolConst(false, false);
 
                            /*
                             * If only one nonconst-or-NULL input, it's the
                             * result
                             */
                            if (list_length(newargs) == 1)
                                return (Node *) linitial(newargs);
                            /* Else we still need an OR node */
                            return (Node *) make_orclause(newargs);
                        }
                    case AND_EXPR:
                        {
                            List       *newargs;
                            bool        haveNull = false;
                            bool        forceFalse = false;
 
                            newargs = simplify_and_arguments(expr->args,
                                                             context,
                                                             &haveNull,
                                                             &forceFalse);
                            if (forceFalse)
                                return makeBoolConst(false, false);
                            if (haveNull)
                                newargs = lappend(newargs,
                                                  makeBoolConst(false, true));
                            /* If all the inputs are TRUE, result is TRUE */
                            if (newargs == NIL)
                                return makeBoolConst(true, false);
 
                            /*
                             * If only one nonconst-or-NULL input, it's the
                             * result
                             */
                            if (list_length(newargs) == 1)
                                return (Node *) linitial(newargs);
                            /* Else we still need an AND node */
                            return (Node *) make_andclause(newargs);
                        }
                    case NOT_EXPR:
                        {
                            Node       *arg;
 
                            Assert(list_length(expr->args) == 1);
                            arg = eval_const_expressions_mutator(linitial(expr->args),
                                                                 context);
 
                            /*
                             * Use negate_clause() to see if we can simplify
                             * away the NOT.
                             */
                            return negate_clause(arg);
                        }
                    default:
                        elog(ERROR, "unrecognized boolop: %d",
                             (int) expr->boolop);
                        break;
                }
                break;
            }
 
        case T_JsonValueExpr:
            {
                JsonValueExpr *jve = (JsonValueExpr *) node;
                Node       *raw_expr = (Node *) jve->raw_expr;
                Node       *formatted_expr = (Node *) jve->formatted_expr;
 
                /*
                 * If we can fold formatted_expr to a constant, we can elide
                 * the JsonValueExpr altogether.  Otherwise we must process
                 * raw_expr too.  But JsonFormat is a flat node and requires
                 * no simplification, only copying.
                 */
                formatted_expr = eval_const_expressions_mutator(formatted_expr,
                                                                context);
                if (formatted_expr && IsA(formatted_expr, Const))
                    return formatted_expr;
 
                raw_expr = eval_const_expressions_mutator(raw_expr, context);
 
                return (Node *) makeJsonValueExpr((Expr *) raw_expr,
                                                  (Expr *) formatted_expr,
                                                  copyObject(jve->format));
            }
 
        case T_SubPlan:
        case T_AlternativeSubPlan:
 
            /*
             * Return a SubPlan unchanged --- too late to do anything with it.
             *
             * XXX should we ereport() here instead?  Probably this routine
             * should never be invoked after SubPlan creation.
             */
            return node;
        case T_RelabelType:
            {
                RelabelType *relabel = (RelabelType *) node;
                Node       *arg;
 
                /* Simplify the input ... */
                arg = eval_const_expressions_mutator((Node *) relabel->arg,
                                                     context);
                /* ... and attach a new RelabelType node, if needed */
                return applyRelabelType(arg,
                                        relabel->resulttype,
                                        relabel->resulttypmod,
                                        relabel->resultcollid,
                                        relabel->relabelformat,
                                        relabel->location,
                                        true);
            }
        case T_CoerceViaIO:
            {
                CoerceViaIO *expr = (CoerceViaIO *) node;
                List       *args;
                Oid         outfunc;
                bool        outtypisvarlena;
                Oid         infunc;
                Oid         intypioparam;
                Expr       *simple;
                CoerceViaIO *newexpr;
 
                /* Make a List so we can use simplify_function */
                args = list_make1(expr->arg);
 
                /*
                 * CoerceViaIO represents calling the source type's output
                 * function then the result type's input function.  So, try to
                 * simplify it as though it were a stack of two such function
                 * calls.  First we need to know what the functions are.
                 *
                 * Note that the coercion functions are assumed not to care
                 * about input collation, so we just pass InvalidOid for that.
                 */
                getTypeOutputInfo(exprType((Node *) expr->arg),
                                  &outfunc, &outtypisvarlena);
                getTypeInputInfo(expr->resulttype,
                                 &infunc, &intypioparam);
 
                simple = simplify_function(outfunc,
                                           CSTRINGOID, -1,
                                           InvalidOid,
                                           InvalidOid,
                                           &args,
                                           false,
                                           true,
                                           true,
                                           context);
                if (simple)     /* successfully simplified output fn */
                {
                    /*
                     * Input functions may want 1 to 3 arguments.  We always
                     * supply all three, trusting that nothing downstream will
                     * complain.
                     */
                    args = list_make3(simple,
                                      makeConst(OIDOID,
                                                -1,
                                                InvalidOid,
                                                sizeof(Oid),
                                                ObjectIdGetDatum(intypioparam),
                                                false,
                                                true),
                                      makeConst(INT4OID,
                                                -1,
                                                InvalidOid,
                                                sizeof(int32),
                                                Int32GetDatum(-1),
                                                false,
                                                true));
 
                    simple = simplify_function(infunc,
                                               expr->resulttype, -1,
                                               expr->resultcollid,
                                               InvalidOid,
                                               &args,
                                               false,
                                               false,
                                               true,
                                               context);
                    if (simple) /* successfully simplified input fn */
                        return (Node *) simple;
                }
 
                /*
                 * The expression cannot be simplified any further, so build
                 * and return a replacement CoerceViaIO node using the
                 * possibly-simplified argument.
                 */
                newexpr = makeNode(CoerceViaIO);
                newexpr->arg = (Expr *) linitial(args);
                newexpr->resulttype = expr->resulttype;
                newexpr->resultcollid = expr->resultcollid;
                newexpr->coerceformat = expr->coerceformat;
                newexpr->location = expr->location;
                return (Node *) newexpr;
            }
        case T_ArrayCoerceExpr:
            {
                ArrayCoerceExpr *ac = makeNode(ArrayCoerceExpr);
                Node       *save_case_val;
 
                /*
                 * Copy the node and const-simplify its arguments.  We can't
                 * use ece_generic_processing() here because we need to mess
                 * with case_val only while processing the elemexpr.
                 */
                memcpy(ac, node, sizeof(ArrayCoerceExpr));
                ac->arg = (Expr *)
                    eval_const_expressions_mutator((Node *) ac->arg,
                                                   context);
 
                /*
                 * Set up for the CaseTestExpr node contained in the elemexpr.
                 * We must prevent it from absorbing any outer CASE value.
                 */
                save_case_val = context->case_val;
                context->case_val = NULL;
 
                ac->elemexpr = (Expr *)
                    eval_const_expressions_mutator((Node *) ac->elemexpr,
                                                   context);
 
                context->case_val = save_case_val;
 
                /*
                 * If constant argument and the per-element expression is
                 * immutable, we can simplify the whole thing to a constant.
                 * Exception: although contain_mutable_functions considers
                 * CoerceToDomain immutable for historical reasons, let's not
                 * do so here; this ensures coercion to an array-over-domain
                 * does not apply the domain's constraints until runtime.
                 */
                if (ac->arg && IsA(ac->arg, Const) &&
                    ac->elemexpr && !IsA(ac->elemexpr, CoerceToDomain) &&
                    !contain_mutable_functions((Node *) ac->elemexpr))
                    return ece_evaluate_expr(ac);
 
                return (Node *) ac;
            }
        case T_CollateExpr:
            {
                /*
                 * We replace CollateExpr with RelabelType, so as to improve
                 * uniformity of expression representation and thus simplify
                 * comparison of expressions.  Hence this looks very nearly
                 * the same as the RelabelType case, and we can apply the same
                 * optimizations to avoid unnecessary RelabelTypes.
                 */
                CollateExpr *collate = (CollateExpr *) node;
                Node       *arg;
 
                /* Simplify the input ... */
                arg = eval_const_expressions_mutator((Node *) collate->arg,
                                                     context);
                /* ... and attach a new RelabelType node, if needed */
                return applyRelabelType(arg,
                                        exprType(arg),
                                        exprTypmod(arg),
                                        collate->collOid,
                                        COERCE_IMPLICIT_CAST,
                                        collate->location,
                                        true);
            }
        case T_CaseExpr:
            {
                /*----------
                 * CASE expressions can be simplified if there are constant
                 * condition clauses:
                 *      FALSE (or NULL): drop the alternative
                 *      TRUE: drop all remaining alternatives
                 * If the first non-FALSE alternative is a constant TRUE,
                 * we can simplify the entire CASE to that alternative's
                 * expression.  If there are no non-FALSE alternatives,
                 * we simplify the entire CASE to the default result (ELSE).
                 *
                 * If we have a simple-form CASE with constant test
                 * expression, we substitute the constant value for contained
                 * CaseTestExpr placeholder nodes, so that we have the
                 * opportunity to reduce constant test conditions.  For
                 * example this allows
                 *      CASE 0 WHEN 0 THEN 1 ELSE 1/0 END
                 * to reduce to 1 rather than drawing a divide-by-0 error.
                 * Note that when the test expression is constant, we don't
                 * have to include it in the resulting CASE; for example
                 *      CASE 0 WHEN x THEN y ELSE z END
                 * is transformed by the parser to
                 *      CASE 0 WHEN CaseTestExpr = x THEN y ELSE z END
                 * which we can simplify to
                 *      CASE WHEN 0 = x THEN y ELSE z END
                 * It is not necessary for the executor to evaluate the "arg"
                 * expression when executing the CASE, since any contained
                 * CaseTestExprs that might have referred to it will have been
                 * replaced by the constant.
                 *----------
                 */
                CaseExpr   *caseexpr = (CaseExpr *) node;
                CaseExpr   *newcase;
                Node       *save_case_val;
                Node       *newarg;
                List       *newargs;
                bool        const_true_cond;
                Node       *defresult = NULL;
                ListCell   *arg;
 
                /* Simplify the test expression, if any */
                newarg = eval_const_expressions_mutator((Node *) caseexpr->arg,
                                                        context);
 
                /* Set up for contained CaseTestExpr nodes */
                save_case_val = context->case_val;
                if (newarg && IsA(newarg, Const))
                {
                    context->case_val = newarg;
                    newarg = NULL;  /* not needed anymore, see above */
                }
                else
                    context->case_val = NULL;
 
                /* Simplify the WHEN clauses */
                newargs = NIL;
                const_true_cond = false;
                foreach(arg, caseexpr->args)
                {
                    CaseWhen   *oldcasewhen = lfirst_node(CaseWhen, arg);
                    Node       *casecond;
                    Node       *caseresult;
 
                    /* Simplify this alternative's test condition */
                    casecond = eval_const_expressions_mutator((Node *) oldcasewhen->expr,
                                                              context);
 
                    /*
                     * If the test condition is constant FALSE (or NULL), then
                     * drop this WHEN clause completely, without processing
                     * the result.
                     */
                    if (casecond && IsA(casecond, Const))
                    {
                        Const      *const_input = (Const *) casecond;
 
                        if (const_input->constisnull ||
                            !DatumGetBool(const_input->constvalue))
                            continue;   /* drop alternative with FALSE cond */
                        /* Else it's constant TRUE */
                        const_true_cond = true;
                    }
 
                    /* Simplify this alternative's result value */
                    caseresult = eval_const_expressions_mutator((Node *) oldcasewhen->result,
                                                                context);
 
                    /* If non-constant test condition, emit a new WHEN node */
                    if (!const_true_cond)
                    {
                        CaseWhen   *newcasewhen = makeNode(CaseWhen);
 
                        newcasewhen->expr = (Expr *) casecond;
                        newcasewhen->result = (Expr *) caseresult;
                        newcasewhen->location = oldcasewhen->location;
                        newargs = lappend(newargs, newcasewhen);
                        continue;
                    }
 
                    /*
                     * Found a TRUE condition, so none of the remaining
                     * alternatives can be reached.  We treat the result as
                     * the default result.
                     */
                    defresult = caseresult;
                    break;
                }
 
                /* Simplify the default result, unless we replaced it above */
                if (!const_true_cond)
                    defresult = eval_const_expressions_mutator((Node *) caseexpr->defresult,
                                                               context);
 
                context->case_val = save_case_val;
 
                /*
                 * If no non-FALSE alternatives, CASE reduces to the default
                 * result
                 */
                if (newargs == NIL)
                    return defresult;
                /* Otherwise we need a new CASE node */
                newcase = makeNode(CaseExpr);
                newcase->casetype = caseexpr->casetype;
                newcase->casecollid = caseexpr->casecollid;
                newcase->arg = (Expr *) newarg;
                newcase->args = newargs;
                newcase->defresult = (Expr *) defresult;
                newcase->location = caseexpr->location;
                return (Node *) newcase;
            }
        case T_CaseTestExpr:
            {
                /*
                 * If we know a constant test value for the current CASE
                 * construct, substitute it for the placeholder.  Else just
                 * return the placeholder as-is.
                 */
                if (context->case_val)
                    return copyObject(context->case_val);
                else
                    return copyObject(node);
            }
        case T_SubscriptingRef:
        case T_ArrayExpr:
        case T_RowExpr:
        case T_MinMaxExpr:
            {
                /*
                 * Generic handling for node types whose own processing is
                 * known to be immutable, and for which we need no smarts
                 * beyond "simplify if all inputs are constants".
                 *
                 * Treating SubscriptingRef this way assumes that subscripting
                 * fetch and assignment are both immutable.  This constrains
                 * type-specific subscripting implementations; maybe we should
                 * relax it someday.
                 *
                 * Treating MinMaxExpr this way amounts to assuming that the
                 * btree comparison function it calls is immutable; see the
                 * reasoning in contain_mutable_functions_walker.
                 */
 
                /* Copy the node and const-simplify its arguments */
                node = ece_generic_processing(node);
                /* If all arguments are Consts, we can fold to a constant */
                if (ece_all_arguments_const(node))
                    return ece_evaluate_expr(node);
                return node;
            }
        case T_CoalesceExpr:
            {
                CoalesceExpr *coalesceexpr = (CoalesceExpr *) node;
                CoalesceExpr *newcoalesce;
                List       *newargs;
                ListCell   *arg;
 
                newargs = NIL;
                foreach(arg, coalesceexpr->args)
                {
                    Node       *e;
 
                    e = eval_const_expressions_mutator((Node *) lfirst(arg),
                                                       context);
 
                    /*
                     * We can remove null constants from the list. For a
                     * non-null constant, if it has not been preceded by any
                     * other non-null-constant expressions then it is the
                     * result. Otherwise, it's the next argument, but we can
                     * drop following arguments since they will never be
                     * reached.
                     */
                    if (IsA(e, Const))
                    {
                        if (((Const *) e)->constisnull)
                            continue;   /* drop null constant */
                        if (newargs == NIL)
                            return e;   /* first expr */
                        newargs = lappend(newargs, e);
                        break;
                    }
                    newargs = lappend(newargs, e);
                }
 
                /*
                 * If all the arguments were constant null, the result is just
                 * null
                 */
                if (newargs == NIL)
                    return (Node *) makeNullConst(coalesceexpr->coalescetype,
                                                  -1,
                                                  coalesceexpr->coalescecollid);
 
                /*
                 * If there's exactly one surviving argument, we no longer
                 * need COALESCE at all: the result is that argument
                 */
                if (list_length(newargs) == 1)
                    return (Node *) linitial(newargs);
 
                newcoalesce = makeNode(CoalesceExpr);
                newcoalesce->coalescetype = coalesceexpr->coalescetype;
                newcoalesce->coalescecollid = coalesceexpr->coalescecollid;
                newcoalesce->args = newargs;
                newcoalesce->location = coalesceexpr->location;
                return (Node *) newcoalesce;
            }
        case T_SQLValueFunction:
            {
                /*
                 * All variants of SQLValueFunction are stable, so if we are
                 * estimating the expression's value, we should evaluate the
                 * current function value.  Otherwise just copy.
                 */
                SQLValueFunction *svf = (SQLValueFunction *) node;
 
                if (context->estimate)
                    return (Node *) evaluate_expr((Expr *) svf,
                                                  svf->type,
                                                  svf->typmod,
                                                  InvalidOid);
                else
                    return copyObject((Node *) svf);
            }
        case T_FieldSelect:
            {
                /*
                 * We can optimize field selection from a whole-row Var into a
                 * simple Var.  (This case won't be generated directly by the
                 * parser, because ParseComplexProjection short-circuits it.
                 * But it can arise while simplifying functions.)  Also, we
                 * can optimize field selection from a RowExpr construct, or
                 * of course from a constant.
                 *
                 * However, replacing a whole-row Var in this way has a
                 * pitfall: if we've already built the rel targetlist for the
                 * source relation, then the whole-row Var is scheduled to be
                 * produced by the relation scan, but the simple Var probably
                 * isn't, which will lead to a failure in setrefs.c.  This is
                 * not a problem when handling simple single-level queries, in
                 * which expression simplification always happens first.  It
                 * is a risk for lateral references from subqueries, though.
                 * To avoid such failures, don't optimize uplevel references.
                 *
                 * We must also check that the declared type of the field is
                 * still the same as when the FieldSelect was created --- this
                 * can change if someone did ALTER COLUMN TYPE on the rowtype.
                 * If it isn't, we skip the optimization; the case will
                 * probably fail at runtime, but that's not our problem here.
                 */
                FieldSelect *fselect = (FieldSelect *) node;
                FieldSelect *newfselect;
                Node       *arg;
 
                arg = eval_const_expressions_mutator((Node *) fselect->arg,
                                                     context);
                if (arg && IsA(arg, Var) &&
                    ((Var *) arg)->varattno == InvalidAttrNumber &&
                    ((Var *) arg)->varlevelsup == 0)
                {
                    if (rowtype_field_matches(((Var *) arg)->vartype,
                                              fselect->fieldnum,
                                              fselect->resulttype,
                                              fselect->resulttypmod,
                                              fselect->resultcollid))
                    {
                        Var        *newvar;
 
                        newvar = makeVar(((Var *) arg)->varno,
                                         fselect->fieldnum,
                                         fselect->resulttype,
                                         fselect->resulttypmod,
                                         fselect->resultcollid,
                                         ((Var *) arg)->varlevelsup);
                        /* New Var has same OLD/NEW returning as old one */
                        newvar->varreturningtype = ((Var *) arg)->varreturningtype;
                        /* New Var is nullable by same rels as the old one */
                        newvar->varnullingrels = ((Var *) arg)->varnullingrels;
                        return (Node *) newvar;
                    }
                }
                if (arg && IsA(arg, RowExpr))
                {
                    RowExpr    *rowexpr = (RowExpr *) arg;
 
                    if (fselect->fieldnum > 0 &&
                        fselect->fieldnum <= list_length(rowexpr->args))
                    {
                        Node       *fld = (Node *) list_nth(rowexpr->args,
                                                            fselect->fieldnum - 1);
 
                        if (rowtype_field_matches(rowexpr->row_typeid,
                                                  fselect->fieldnum,
                                                  fselect->resulttype,
                                                  fselect->resulttypmod,
                                                  fselect->resultcollid) &&
                            fselect->resulttype == exprType(fld) &&
                            fselect->resulttypmod == exprTypmod(fld) &&
                            fselect->resultcollid == exprCollation(fld))
                            return fld;
                    }
                }
                newfselect = makeNode(FieldSelect);
                newfselect->arg = (Expr *) arg;
                newfselect->fieldnum = fselect->fieldnum;
                newfselect->resulttype = fselect->resulttype;
                newfselect->resulttypmod = fselect->resulttypmod;
                newfselect->resultcollid = fselect->resultcollid;
                if (arg && IsA(arg, Const))
                {
                    Const      *con = (Const *) arg;
 
                    if (rowtype_field_matches(con->consttype,
                                              newfselect->fieldnum,
                                              newfselect->resulttype,
                                              newfselect->resulttypmod,
                                              newfselect->resultcollid))
                        return ece_evaluate_expr(newfselect);
                }
                return (Node *) newfselect;
            }
        case T_NullTest:
            {
                NullTest   *ntest = (NullTest *) node;
                NullTest   *newntest;
                Node       *arg;
 
                arg = eval_const_expressions_mutator((Node *) ntest->arg,
                                                     context);
                if (ntest->argisrow && arg && IsA(arg, RowExpr))
                {
                    /*
                     * We break ROW(...) IS [NOT] NULL into separate tests on
                     * its component fields.  This form is usually more
                     * efficient to evaluate, as well as being more amenable
                     * to optimization.
                     */
                    RowExpr    *rarg = (RowExpr *) arg;
                    List       *newargs = NIL;
                    ListCell   *l;
 
                    foreach(l, rarg->args)
                    {
                        Node       *relem = (Node *) lfirst(l);
 
                        /*
                         * A constant field refutes the whole NullTest if it's
                         * of the wrong nullness; else we can discard it.
                         */
                        if (relem && IsA(relem, Const))
                        {
                            Const      *carg = (Const *) relem;
 
                            if (carg->constisnull ?
                                (ntest->nulltesttype == IS_NOT_NULL) :
                                (ntest->nulltesttype == IS_NULL))
                                return makeBoolConst(false, false);
                            continue;
                        }
 
                        /*
                         * Else, make a scalar (argisrow == false) NullTest
                         * for this field.  Scalar semantics are required
                         * because IS [NOT] NULL doesn't recurse; see comments
                         * in ExecEvalRowNullInt().
                         */
                        newntest = makeNode(NullTest);
                        newntest->arg = (Expr *) relem;
                        newntest->nulltesttype = ntest->nulltesttype;
                        newntest->argisrow = false;
                        newntest->location = ntest->location;
                        newargs = lappend(newargs, newntest);
                    }
                    /* If all the inputs were constants, result is TRUE */
                    if (newargs == NIL)
                        return makeBoolConst(true, false);
                    /* If only one nonconst input, it's the result */
                    if (list_length(newargs) == 1)
                        return (Node *) linitial(newargs);
                    /* Else we need an AND node */
                    return (Node *) make_andclause(newargs);
                }
                if (!ntest->argisrow && arg && IsA(arg, Const))
                {
                    Const      *carg = (Const *) arg;
                    bool        result;
 
                    switch (ntest->nulltesttype)
                    {
                        case IS_NULL:
                            result = carg->constisnull;
                            break;
                        case IS_NOT_NULL:
                            result = !carg->constisnull;
                            break;
                        default:
                            elog(ERROR, "unrecognized nulltesttype: %d",
                                 (int) ntest->nulltesttype);
                            result = false; /* keep compiler quiet */
                            break;
                    }
 
                    return makeBoolConst(result, false);
                }
                if (!ntest->argisrow && arg && IsA(arg, Var) && context->root)
                {
                    Var        *varg = (Var *) arg;
                    bool        result;
 
                    if (var_is_nonnullable(context->root, varg, false))
                    {
                        switch (ntest->nulltesttype)
                        {
                            case IS_NULL:
                                result = false;
                                break;
                            case IS_NOT_NULL:
                                result = true;
                                break;
                            default:
                                elog(ERROR, "unrecognized nulltesttype: %d",
                                     (int) ntest->nulltesttype);
                                result = false; /* keep compiler quiet */
                                break;
                        }
 
                        return makeBoolConst(result, false);
                    }
                }
 
                newntest = makeNode(NullTest);
                newntest->arg = (Expr *) arg;
                newntest->nulltesttype = ntest->nulltesttype;
                newntest->argisrow = ntest->argisrow;
                newntest->location = ntest->location;
                return (Node *) newntest;
            }
        case T_BooleanTest:
            {
                /*
                 * This case could be folded into the generic handling used
                 * for ArrayExpr etc.  But because the simplification logic is
                 * so trivial, applying evaluate_expr() to perform it would be
                 * a heavy overhead.  BooleanTest is probably common enough to
                 * justify keeping this bespoke implementation.
                 */
                BooleanTest *btest = (BooleanTest *) node;
                BooleanTest *newbtest;
                Node       *arg;
 
                arg = eval_const_expressions_mutator((Node *) btest->arg,
                                                     context);
                if (arg && IsA(arg, Const))
                {
                    Const      *carg = (Const *) arg;
                    bool        result;
 
                    switch (btest->booltesttype)
                    {
                        case IS_TRUE:
                            result = (!carg->constisnull &&
                                      DatumGetBool(carg->constvalue));
                            break;
                        case IS_NOT_TRUE:
                            result = (carg->constisnull ||
                                      !DatumGetBool(carg->constvalue));
                            break;
                        case IS_FALSE:
                            result = (!carg->constisnull &&
                                      !DatumGetBool(carg->constvalue));
                            break;
                        case IS_NOT_FALSE:
                            result = (carg->constisnull ||
                                      DatumGetBool(carg->constvalue));
                            break;
                        case IS_UNKNOWN:
                            result = carg->constisnull;
                            break;
                        case IS_NOT_UNKNOWN:
                            result = !carg->constisnull;
                            break;
                        default:
                            elog(ERROR, "unrecognized booltesttype: %d",
                                 (int) btest->booltesttype);
                            result = false; /* keep compiler quiet */
                            break;
                    }
 
                    return makeBoolConst(result, false);
                }
 
                newbtest = makeNode(BooleanTest);
                newbtest->arg = (Expr *) arg;
                newbtest->booltesttype = btest->booltesttype;
                newbtest->location = btest->location;
                return (Node *) newbtest;
            }
        case T_CoerceToDomain:
            {
                /*
                 * If the domain currently has no constraints, we replace the
                 * CoerceToDomain node with a simple RelabelType, which is
                 * both far faster to execute and more amenable to later
                 * optimization.  We must then mark the plan as needing to be
                 * rebuilt if the domain's constraints change.
                 *
                 * Also, in estimation mode, always replace CoerceToDomain
                 * nodes, effectively assuming that the coercion will succeed.
                 */
                CoerceToDomain *cdomain = (CoerceToDomain *) node;
                CoerceToDomain *newcdomain;
                Node       *arg;
 
                arg = eval_const_expressions_mutator((Node *) cdomain->arg,
                                                     context);
                if (context->estimate ||
                    !DomainHasConstraints(cdomain->resulttype))
                {
                    /* Record dependency, if this isn't estimation mode */
                    if (context->root && !context->estimate)
                        record_plan_type_dependency(context->root,
                                                    cdomain->resulttype);
 
                    /* Generate RelabelType to substitute for CoerceToDomain */
                    return applyRelabelType(arg,
                                            cdomain->resulttype,
                                            cdomain->resulttypmod,
                                            cdomain->resultcollid,
                                            cdomain->coercionformat,
                                            cdomain->location,
                                            true);
                }
 
                newcdomain = makeNode(CoerceToDomain);
                newcdomain->arg = (Expr *) arg;
                newcdomain->resulttype = cdomain->resulttype;
                newcdomain->resulttypmod = cdomain->resulttypmod;
                newcdomain->resultcollid = cdomain->resultcollid;
                newcdomain->coercionformat = cdomain->coercionformat;
                newcdomain->location = cdomain->location;
                return (Node *) newcdomain;
            }
        case T_PlaceHolderVar:
 
            /*
             * In estimation mode, just strip the PlaceHolderVar node
             * altogether; this amounts to estimating that the contained value
             * won't be forced to null by an outer join.  In regular mode we
             * just use the default behavior (ie, simplify the expression but
             * leave the PlaceHolderVar node intact).
             */
            if (context->estimate)
            {
                PlaceHolderVar *phv = (PlaceHolderVar *) node;
 
                return eval_const_expressions_mutator((Node *) phv->phexpr,
                                                      context);
            }
            break;
        case T_ConvertRowtypeExpr:
            {
                ConvertRowtypeExpr *cre = castNode(ConvertRowtypeExpr, node);
                Node       *arg;
                ConvertRowtypeExpr *newcre;
 
                arg = eval_const_expressions_mutator((Node *) cre->arg,
                                                     context);
 
                newcre = makeNode(ConvertRowtypeExpr);
                newcre->resulttype = cre->resulttype;
                newcre->convertformat = cre->convertformat;
                newcre->location = cre->location;
 
                /*
                 * In case of a nested ConvertRowtypeExpr, we can convert the
                 * leaf row directly to the topmost row format without any
                 * intermediate conversions. (This works because
                 * ConvertRowtypeExpr is used only for child->parent
                 * conversion in inheritance trees, which works by exact match
                 * of column name, and a column absent in an intermediate
                 * result can't be present in the final result.)
                 *
                 * No need to check more than one level deep, because the
                 * above recursion will have flattened anything else.
                 */
                if (arg != NULL && IsA(arg, ConvertRowtypeExpr))
                {
                    ConvertRowtypeExpr *argcre = (ConvertRowtypeExpr *) arg;
 
                    arg = (Node *) argcre->arg;
 
                    /*
                     * Make sure an outer implicit conversion can't hide an
                     * inner explicit one.
                     */
                    if (newcre->convertformat == COERCE_IMPLICIT_CAST)
                        newcre->convertformat = argcre->convertformat;
                }
 
                newcre->arg = (Expr *) arg;
 
                if (arg != NULL && IsA(arg, Const))
                    return ece_evaluate_expr((Node *) newcre);
                return (Node *) newcre;
            }
        default:
            break;
    }
 
    /*
     * For any node type not handled above, copy the node unchanged but
     * const-simplify its subexpressions.  This is the correct thing for node
     * types whose behavior might change between planning and execution, such
     * as CurrentOfExpr.  It's also a safe default for new node types not
     * known to this routine.
     */
    return ece_generic_processing(node);
}

References WindowFunc::aggfilter, AND_EXPR, applyRelabelType(), arg, FieldSelect::arg, RelabelType::arg, CoerceViaIO::arg, ArrayCoerceExpr::arg, ConvertRowtypeExpr::arg, CollateExpr::arg, CaseExpr::arg, NullTest::arg, BooleanTest::arg, CoerceToDomain::arg, generate_unaccent_rules::args, WindowFunc::args, FuncExpr::args, OpExpr::args, BoolExpr::args, CaseExpr::args, RowExpr::args, CoalesceExpr::args, Assert(), BoolGetDatum(), BoolExpr::boolop, BooleanTest::booltesttype, eval_const_expressions_context::boundParams, eval_const_expressions_context::case_val, castNode, check_stack_depth(), COERCE_IMPLICIT_CAST, CollateExpr::collOid, Const::consttype, contain_mutable_functions(), copyObject, datumCopy(), DatumGetBool(), CaseExpr::defresult, DomainHasConstraints(), ece_all_arguments_const, ece_evaluate_expr, ece_function_is_safe(), ece_generic_processing, ArrayCoerceExpr::elemexpr, elog, ERROR, eval_const_expressions_context::estimate, eval_const_expressions_mutator(), evaluate_expr(), expand_function_arguments(), CaseWhen::expr, exprCollation(), expression_tree_mutator, exprType(), exprTypmod(), FieldSelect::fieldnum, JsonValueExpr::format, JsonValueExpr::formatted_expr, FuncExpr::funcid, get_typlenbyval(), getTypeInputInfo(), getTypeOutputInfo(), HeapTupleIsValid, if(), WindowFunc::ignore_nulls, Int32GetDatum(), InvalidAttrNumber, InvalidOid, IS_FALSE, IS_NOT_FALSE, IS_NOT_NULL, IS_NOT_TRUE, IS_NOT_UNKNOWN, IS_NULL, IS_TRUE, IS_UNKNOWN, IsA, ParamExternData::isnull, lappend(), lfirst, lfirst_node, linitial, list_length(), list_make1, list_make3, list_nth(), Param::location, WindowFunc::location, FuncExpr::location, OpExpr::location, RelabelType::location, CoerceViaIO::location, ConvertRowtypeExpr::location, CollateExpr::location, CaseExpr::location, CaseWhen::location, CoalesceExpr::location, NullTest::location, BooleanTest::location, CoerceToDomain::location, make_andclause(), make_orclause(), makeBoolConst(), makeConst(), makeJsonValueExpr(), makeNode, makeNullConst(), makeVar(), negate_clause(), NIL, nodeTag, NOT_EXPR, NullTest::nulltesttype, ParamListInfoData::numParams, ObjectIdGetDatum(), OidIsValid, OpExpr::opno, OR_EXPR, PARAM_EXTERN, PARAM_FLAG_CONST, Param::paramcollid, ParamListInfoData::paramFetch, Param::paramid, Param::paramkind, ParamListInfoData::params, Param::paramtype, Param::paramtypmod, ParamExternData::pflags, ParamExternData::ptype, JsonValueExpr::raw_expr, record_plan_type_dependency(), ReleaseSysCache(), CaseWhen::result, RelabelType::resulttype, CoerceViaIO::resulttype, ConvertRowtypeExpr::resulttype, CoerceToDomain::resulttype, eval_const_expressions_context::root, rowtype_field_matches(), SearchSysCache1(), set_opfuncid(), set_sa_opfuncid(), simplify_and_arguments(), simplify_boolean_equality(), simplify_function(), simplify_or_arguments(), SQLValueFunction::typmod, ParamExternData::value, var_is_nonnullable(), Var::varreturningtype, WindowFunc::winfnoid, and WindowFunc::winref.

Referenced by estimate_expression_value(), eval_const_expressions(), eval_const_expressions_mutator(), inline_function(), simplify_and_arguments(), simplify_function(), and simplify_or_arguments().

evaluate_expr()

Expr * evaluate_expr	(	Expr *	expr,
		Oid	result_type,
		int32	result_typmod,
		Oid	result_collation
	)

Definition at line 5076 of file clauses.c.

{
    EState     *estate;
    ExprState  *exprstate;
    MemoryContext oldcontext;
    Datum       const_val;
    bool        const_is_null;
    int16       resultTypLen;
    bool        resultTypByVal;
 
    /*
     * To use the executor, we need an EState.
     */
    estate = CreateExecutorState();
 
    /* We can use the estate's working context to avoid memory leaks. */
    oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
 
    /* Make sure any opfuncids are filled in. */
    fix_opfuncids((Node *) expr);
 
    /*
     * Prepare expr for execution.  (Note: we can't use ExecPrepareExpr
     * because it'd result in recursively invoking eval_const_expressions.)
     */
    exprstate = ExecInitExpr(expr, NULL);
 
    /*
     * And evaluate it.
     *
     * It is OK to use a default econtext because none of the ExecEvalExpr()
     * code used in this situation will use econtext.  That might seem
     * fortuitous, but it's not so unreasonable --- a constant expression does
     * not depend on context, by definition, n'est ce pas?
     */
    const_val = ExecEvalExprSwitchContext(exprstate,
                                          GetPerTupleExprContext(estate),
                                          &const_is_null);
 
    /* Get info needed about result datatype */
    get_typlenbyval(result_type, &resultTypLen, &resultTypByVal);
 
    /* Get back to outer memory context */
    MemoryContextSwitchTo(oldcontext);
 
    /*
     * Must copy result out of sub-context used by expression eval.
     *
     * Also, if it's varlena, forcibly detoast it.  This protects us against
     * storing TOAST pointers into plans that might outlive the referenced
     * data.  (makeConst would handle detoasting anyway, but it's worth a few
     * extra lines here so that we can do the copy and detoast in one step.)
     */
    if (!const_is_null)
    {
        if (resultTypLen == -1)
            const_val = PointerGetDatum(PG_DETOAST_DATUM_COPY(const_val));
        else
            const_val = datumCopy(const_val, resultTypByVal, resultTypLen);
    }
 
    /* Release all the junk we just created */
    FreeExecutorState(estate);
 
    /*
     * Make the constant result node.
     */
    return (Expr *) makeConst(result_type, result_typmod, result_collation,
                              resultTypLen,
                              const_val, const_is_null,
                              resultTypByVal);
}

References CreateExecutorState(), datumCopy(), EState::es_query_cxt, ExecEvalExprSwitchContext(), ExecInitExpr(), fix_opfuncids(), FreeExecutorState(), get_typlenbyval(), GetPerTupleExprContext, makeConst(), MemoryContextSwitchTo(), PG_DETOAST_DATUM_COPY, and PointerGetDatum().

Referenced by eval_const_expressions_mutator(), evaluate_function(), and transformPartitionBoundValue().

evaluate_function()

static Expr * evaluate_function ( Oid  funcid, Oid  result_type, int32  result_typmod, Oid  result_collid, Oid  input_collid, List *  args, bool  funcvariadic, HeapTuple  func_tuple, eval_const_expressions_context *  context  )

static

Definition at line 4529 of file clauses.c.

{
    Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
    bool        has_nonconst_input = false;
    bool        has_null_input = false;
    ListCell   *arg;
    FuncExpr   *newexpr;
 
    /*
     * Can't simplify if it returns a set.
     */
    if (funcform->proretset)
        return NULL;
 
    /*
     * Can't simplify if it returns RECORD.  The immediate problem is that it
     * will be needing an expected tupdesc which we can't supply here.
     *
     * In the case where it has OUT parameters, we could build an expected
     * tupdesc from those, but there may be other gotchas lurking.  In
     * particular, if the function were to return NULL, we would produce a
     * null constant with no remaining indication of which concrete record
     * type it is.  For now, seems best to leave the function call unreduced.
     */
    if (funcform->prorettype == RECORDOID)
        return NULL;
 
    /*
     * Check for constant inputs and especially constant-NULL inputs.
     */
    foreach(arg, args)
    {
        if (IsA(lfirst(arg), Const))
            has_null_input |= ((Const *) lfirst(arg))->constisnull;
        else
            has_nonconst_input = true;
    }
 
    /*
     * If the function is strict and has a constant-NULL input, it will never
     * be called at all, so we can replace the call by a NULL constant, even
     * if there are other inputs that aren't constant, and even if the
     * function is not otherwise immutable.
     */
    if (funcform->proisstrict && has_null_input)
        return (Expr *) makeNullConst(result_type, result_typmod,
                                      result_collid);
 
    /*
     * Otherwise, can simplify only if all inputs are constants. (For a
     * non-strict function, constant NULL inputs are treated the same as
     * constant non-NULL inputs.)
     */
    if (has_nonconst_input)
        return NULL;
 
    /*
     * Ordinarily we are only allowed to simplify immutable functions. But for
     * purposes of estimation, we consider it okay to simplify functions that
     * are merely stable; the risk that the result might change from planning
     * time to execution time is worth taking in preference to not being able
     * to estimate the value at all.
     */
    if (funcform->provolatile == PROVOLATILE_IMMUTABLE)
         /* okay */ ;
    else if (context->estimate && funcform->provolatile == PROVOLATILE_STABLE)
         /* okay */ ;
    else
        return NULL;
 
    /*
     * OK, looks like we can simplify this operator/function.
     *
     * Build a new FuncExpr node containing the already-simplified arguments.
     */
    newexpr = makeNode(FuncExpr);
    newexpr->funcid = funcid;
    newexpr->funcresulttype = result_type;
    newexpr->funcretset = false;
    newexpr->funcvariadic = funcvariadic;
    newexpr->funcformat = COERCE_EXPLICIT_CALL; /* doesn't matter */
    newexpr->funccollid = result_collid;    /* doesn't matter */
    newexpr->inputcollid = input_collid;
    newexpr->args = args;
    newexpr->location = -1;
 
    return evaluate_expr((Expr *) newexpr, result_type, result_typmod,
                         result_collid);
}

References arg, generate_unaccent_rules::args, FuncExpr::args, COERCE_EXPLICIT_CALL, eval_const_expressions_context::estimate, evaluate_expr(), FuncExpr::funcid, GETSTRUCT(), IsA, lfirst, FuncExpr::location, makeNode, and makeNullConst().

Referenced by simplify_function().

expand_function_arguments()

List * expand_function_arguments	(	List *	args,
		bool	include_out_arguments,
		Oid	result_type,
		HeapTuple	func_tuple
	)

Definition at line 4279 of file clauses.c.

{
    Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
    Oid        *proargtypes = funcform->proargtypes.values;
    int         pronargs = funcform->pronargs;
    bool        has_named_args = false;
    ListCell   *lc;
 
    /*
     * If we are asked to match to OUT arguments, then use the proallargtypes
     * array (which includes those); otherwise use proargtypes (which
     * doesn't).  Of course, if proallargtypes is null, we always use
     * proargtypes.  (Fetching proallargtypes is annoyingly expensive
     * considering that we may have nothing to do here, but fortunately the
     * common case is include_out_arguments == false.)
     */
    if (include_out_arguments)
    {
        Datum       proallargtypes;
        bool        isNull;
 
        proallargtypes = SysCacheGetAttr(PROCOID, func_tuple,
                                         Anum_pg_proc_proallargtypes,
                                         &isNull);
        if (!isNull)
        {
            ArrayType  *arr = DatumGetArrayTypeP(proallargtypes);
 
            pronargs = ARR_DIMS(arr)[0];
            if (ARR_NDIM(arr) != 1 ||
                pronargs < 0 ||
                ARR_HASNULL(arr) ||
                ARR_ELEMTYPE(arr) != OIDOID)
                elog(ERROR, "proallargtypes is not a 1-D Oid array or it contains nulls");
            Assert(pronargs >= funcform->pronargs);
            proargtypes = (Oid *) ARR_DATA_PTR(arr);
        }
    }
 
    /* Do we have any named arguments? */
    foreach(lc, args)
    {
        Node       *arg = (Node *) lfirst(lc);
 
        if (IsA(arg, NamedArgExpr))
        {
            has_named_args = true;
            break;
        }
    }
 
    /* If so, we must apply reorder_function_arguments */
    if (has_named_args)
    {
        args = reorder_function_arguments(args, pronargs, func_tuple);
        /* Recheck argument types and add casts if needed */
        recheck_cast_function_args(args, result_type,
                                   proargtypes, pronargs,
                                   func_tuple);
    }
    else if (list_length(args) < pronargs)
    {
        /* No named args, but we seem to be short some defaults */
        args = add_function_defaults(args, pronargs, func_tuple);
        /* Recheck argument types and add casts if needed */
        recheck_cast_function_args(args, result_type,
                                   proargtypes, pronargs,
                                   func_tuple);
    }
 
    return args;
}

References add_function_defaults(), arg, generate_unaccent_rules::args, ARR_DATA_PTR, ARR_DIMS, ARR_ELEMTYPE, ARR_HASNULL, ARR_NDIM, Assert(), DatumGetArrayTypeP, elog, ERROR, GETSTRUCT(), IsA, lfirst, list_length(), pronargs, recheck_cast_function_args(), reorder_function_arguments(), and SysCacheGetAttr().

Referenced by eval_const_expressions_mutator(), simplify_function(), and transformCallStmt().

expression_returns_set_rows()

double expression_returns_set_rows	(	PlannerInfo *	root,
		Node *	clause
	)

Definition at line 293 of file clauses.c.

{
    if (clause == NULL)
        return 1.0;
    if (IsA(clause, FuncExpr))
    {
        FuncExpr   *expr = (FuncExpr *) clause;
 
        if (expr->funcretset)
            return clamp_row_est(get_function_rows(root, expr->funcid, clause));
    }
    if (IsA(clause, OpExpr))
    {
        OpExpr     *expr = (OpExpr *) clause;
 
        if (expr->opretset)
        {
            set_opfuncid(expr);
            return clamp_row_est(get_function_rows(root, expr->opfuncid, clause));
        }
    }
    return 1.0;
}

References clamp_row_est(), FuncExpr::funcid, get_function_rows(), IsA, root, and set_opfuncid().

Referenced by create_set_projection_path(), estimate_num_groups(), and set_function_size_estimates().

fetch_function_defaults()

static List * fetch_function_defaults ( HeapTuple  func_tuple )

static

Definition at line 4454 of file clauses.c.

{
    List       *defaults;
    Datum       proargdefaults;
    char       *str;
 
    proargdefaults = SysCacheGetAttrNotNull(PROCOID, func_tuple,
                                            Anum_pg_proc_proargdefaults);
    str = TextDatumGetCString(proargdefaults);
    defaults = castNode(List, stringToNode(str));
    pfree(str);
    return defaults;
}

References castNode, pfree(), str, stringToNode(), SysCacheGetAttrNotNull(), and TextDatumGetCString.

Referenced by add_function_defaults(), and reorder_function_arguments().

find_forced_null_var()

Var * find_forced_null_var

(

Node *

node

)

Definition at line 1984 of file clauses.c.

{
    if (node == NULL)
        return NULL;
    if (IsA(node, NullTest))
    {
        /* check for var IS NULL */
        NullTest   *expr = (NullTest *) node;
 
        if (expr->nulltesttype == IS_NULL && !expr->argisrow)
        {
            Var        *var = (Var *) expr->arg;
 
            if (var && IsA(var, Var) &&
                var->varlevelsup == 0)
                return var;
        }
    }
    else if (IsA(node, BooleanTest))
    {
        /* var IS UNKNOWN is equivalent to var IS NULL */
        BooleanTest *expr = (BooleanTest *) node;
 
        if (expr->booltesttype == IS_UNKNOWN)
        {
            Var        *var = (Var *) expr->arg;
 
            if (var && IsA(var, Var) &&
                var->varlevelsup == 0)
                return var;
        }
    }
    return NULL;
}

References NullTest::arg, BooleanTest::arg, BooleanTest::booltesttype, if(), IS_NULL, IS_UNKNOWN, IsA, NullTest::nulltesttype, and Var::varlevelsup.

Referenced by check_redundant_nullability_qual(), and find_forced_null_vars().

find_forced_null_vars()

List * find_forced_null_vars

(

Node *

node

)

Definition at line 1923 of file clauses.c.

{
    List       *result = NIL;
    Var        *var;
    ListCell   *l;
 
    if (node == NULL)
        return NIL;
    /* Check single-clause cases using subroutine */
    var = find_forced_null_var(node);
    if (var)
    {
        result = mbms_add_member(result,
                                 var->varno,
                                 var->varattno - FirstLowInvalidHeapAttributeNumber);
    }
    /* Otherwise, handle AND-conditions */
    else if (IsA(node, List))
    {
        /*
         * At top level, we are examining an implicit-AND list: if any of the
         * arms produces FALSE-or-NULL then the result is FALSE-or-NULL.
         */
        foreach(l, (List *) node)
        {
            result = mbms_add_members(result,
                                      find_forced_null_vars((Node *) lfirst(l)));
        }
    }
    else if (IsA(node, BoolExpr))
    {
        BoolExpr   *expr = (BoolExpr *) node;
 
        /*
         * We don't bother considering the OR case, because it's fairly
         * unlikely anyone would write "v1 IS NULL OR v1 IS NULL". Likewise,
         * the NOT case isn't worth expending code on.
         */
        if (expr->boolop == AND_EXPR)
        {
            /* At top level we can just recurse (to the List case) */
            result = find_forced_null_vars((Node *) expr->args);
        }
    }
    return result;
}

References AND_EXPR, BoolExpr::args, BoolExpr::boolop, find_forced_null_var(), find_forced_null_vars(), FirstLowInvalidHeapAttributeNumber, IsA, lfirst, mbms_add_member(), mbms_add_members(), NIL, Var::varattno, and Var::varno.

Referenced by find_forced_null_vars(), and reduce_outer_joins_pass2().

find_nonnullable_rels()

Relids find_nonnullable_rels

(

Node *

clause

)

Definition at line 1463 of file clauses.c.

{
    return find_nonnullable_rels_walker(clause, true);
}

References find_nonnullable_rels_walker().

Referenced by make_outerjoininfo(), and reduce_outer_joins_pass2().

find_nonnullable_rels_walker()

static Relids find_nonnullable_rels_walker ( Node *  node, bool  top_level  )

static

Definition at line 1469 of file clauses.c.

{
    Relids      result = NULL;
    ListCell   *l;
 
    if (node == NULL)
        return NULL;
    if (IsA(node, Var))
    {
        Var        *var = (Var *) node;
 
        if (var->varlevelsup == 0)
            result = bms_make_singleton(var->varno);
    }
    else if (IsA(node, List))
    {
        /*
         * At top level, we are examining an implicit-AND list: if any of the
         * arms produces FALSE-or-NULL then the result is FALSE-or-NULL. If
         * not at top level, we are examining the arguments of a strict
         * function: if any of them produce NULL then the result of the
         * function must be NULL.  So in both cases, the set of nonnullable
         * rels is the union of those found in the arms, and we pass down the
         * top_level flag unmodified.
         */
        foreach(l, (List *) node)
        {
            result = bms_join(result,
                              find_nonnullable_rels_walker(lfirst(l),
                                                           top_level));
        }
    }
    else if (IsA(node, FuncExpr))
    {
        FuncExpr   *expr = (FuncExpr *) node;
 
        if (func_strict(expr->funcid))
            result = find_nonnullable_rels_walker((Node *) expr->args, false);
    }
    else if (IsA(node, OpExpr))
    {
        OpExpr     *expr = (OpExpr *) node;
 
        set_opfuncid(expr);
        if (func_strict(expr->opfuncid))
            result = find_nonnullable_rels_walker((Node *) expr->args, false);
    }
    else if (IsA(node, ScalarArrayOpExpr))
    {
        ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node;
 
        if (is_strict_saop(expr, true))
            result = find_nonnullable_rels_walker((Node *) expr->args, false);
    }
    else if (IsA(node, BoolExpr))
    {
        BoolExpr   *expr = (BoolExpr *) node;
 
        switch (expr->boolop)
        {
            case AND_EXPR:
                /* At top level we can just recurse (to the List case) */
                if (top_level)
                {
                    result = find_nonnullable_rels_walker((Node *) expr->args,
                                                          top_level);
                    break;
                }
 
                /*
                 * Below top level, even if one arm produces NULL, the result
                 * could be FALSE (hence not NULL).  However, if *all* the
                 * arms produce NULL then the result is NULL, so we can take
                 * the intersection of the sets of nonnullable rels, just as
                 * for OR.  Fall through to share code.
                 */
                /* FALL THRU */
            case OR_EXPR:
 
                /*
                 * OR is strict if all of its arms are, so we can take the
                 * intersection of the sets of nonnullable rels for each arm.
                 * This works for both values of top_level.
                 */
                foreach(l, expr->args)
                {
                    Relids      subresult;
 
                    subresult = find_nonnullable_rels_walker(lfirst(l),
                                                             top_level);
                    if (result == NULL) /* first subresult? */
                        result = subresult;
                    else
                        result = bms_int_members(result, subresult);
 
                    /*
                     * If the intersection is empty, we can stop looking. This
                     * also justifies the test for first-subresult above.
                     */
                    if (bms_is_empty(result))
                        break;
                }
                break;
            case NOT_EXPR:
                /* NOT will return null if its arg is null */
                result = find_nonnullable_rels_walker((Node *) expr->args,
                                                      false);
                break;
            default:
                elog(ERROR, "unrecognized boolop: %d", (int) expr->boolop);
                break;
        }
    }
    else if (IsA(node, RelabelType))
    {
        RelabelType *expr = (RelabelType *) node;
 
        result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
    }
    else if (IsA(node, CoerceViaIO))
    {
        /* not clear this is useful, but it can't hurt */
        CoerceViaIO *expr = (CoerceViaIO *) node;
 
        result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
    }
    else if (IsA(node, ArrayCoerceExpr))
    {
        /* ArrayCoerceExpr is strict at the array level; ignore elemexpr */
        ArrayCoerceExpr *expr = (ArrayCoerceExpr *) node;
 
        result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
    }
    else if (IsA(node, ConvertRowtypeExpr))
    {
        /* not clear this is useful, but it can't hurt */
        ConvertRowtypeExpr *expr = (ConvertRowtypeExpr *) node;
 
        result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
    }
    else if (IsA(node, CollateExpr))
    {
        CollateExpr *expr = (CollateExpr *) node;
 
        result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
    }
    else if (IsA(node, NullTest))
    {
        /* IS NOT NULL can be considered strict, but only at top level */
        NullTest   *expr = (NullTest *) node;
 
        if (top_level && expr->nulltesttype == IS_NOT_NULL && !expr->argisrow)
            result = find_nonnullable_rels_walker((Node *) expr->arg, false);
    }
    else if (IsA(node, BooleanTest))
    {
        /* Boolean tests that reject NULL are strict at top level */
        BooleanTest *expr = (BooleanTest *) node;
 
        if (top_level &&
            (expr->booltesttype == IS_TRUE ||
             expr->booltesttype == IS_FALSE ||
             expr->booltesttype == IS_NOT_UNKNOWN))
            result = find_nonnullable_rels_walker((Node *) expr->arg, false);
    }
    else if (IsA(node, SubPlan))
    {
        SubPlan    *splan = (SubPlan *) node;
 
        /*
         * For some types of SubPlan, we can infer strictness from Vars in the
         * testexpr (the LHS of the original SubLink).
         *
         * For ANY_SUBLINK, if the subquery produces zero rows, the result is
         * always FALSE.  If the subquery produces more than one row, the
         * per-row results of the testexpr are combined using OR semantics.
         * Hence ANY_SUBLINK can be strict only at top level, but there it's
         * as strict as the testexpr is.
         *
         * For ROWCOMPARE_SUBLINK, if the subquery produces zero rows, the
         * result is always NULL.  Otherwise, the result is as strict as the
         * testexpr is.  So we can check regardless of top_level.
         *
         * We can't prove anything for other sublink types (in particular,
         * note that ALL_SUBLINK will return TRUE if the subquery is empty).
         */
        if ((top_level && splan->subLinkType == ANY_SUBLINK) ||
            splan->subLinkType == ROWCOMPARE_SUBLINK)
            result = find_nonnullable_rels_walker(splan->testexpr, top_level);
    }
    else if (IsA(node, PlaceHolderVar))
    {
        PlaceHolderVar *phv = (PlaceHolderVar *) node;
 
        /*
         * If the contained expression forces any rels non-nullable, so does
         * the PHV.
         */
        result = find_nonnullable_rels_walker((Node *) phv->phexpr, top_level);
 
        /*
         * If the PHV's syntactic scope is exactly one rel, it will be forced
         * to be evaluated at that rel, and so it will behave like a Var of
         * that rel: if the rel's entire output goes to null, so will the PHV.
         * (If the syntactic scope is a join, we know that the PHV will go to
         * null if the whole join does; but that is AND semantics while we
         * need OR semantics for find_nonnullable_rels' result, so we can't do
         * anything with the knowledge.)
         */
        if (phv->phlevelsup == 0 &&
            bms_membership(phv->phrels) == BMS_SINGLETON)
            result = bms_add_members(result, phv->phrels);
    }
    return result;
}

References AND_EXPR, ANY_SUBLINK, RelabelType::arg, CoerceViaIO::arg, ArrayCoerceExpr::arg, ConvertRowtypeExpr::arg, CollateExpr::arg, NullTest::arg, BooleanTest::arg, FuncExpr::args, OpExpr::args, ScalarArrayOpExpr::args, BoolExpr::args, bms_add_members(), bms_int_members(), bms_is_empty, bms_join(), bms_make_singleton(), bms_membership(), BMS_SINGLETON, BoolExpr::boolop, BooleanTest::booltesttype, elog, ERROR, find_nonnullable_rels_walker(), func_strict(), FuncExpr::funcid, IS_FALSE, IS_NOT_NULL, IS_NOT_UNKNOWN, is_strict_saop(), IS_TRUE, IsA, lfirst, NOT_EXPR, NullTest::nulltesttype, OR_EXPR, PlaceHolderVar::phlevelsup, ROWCOMPARE_SUBLINK, set_opfuncid(), SubPlan::subLinkType, SubPlan::testexpr, Var::varlevelsup, and Var::varno.

Referenced by find_nonnullable_rels(), and find_nonnullable_rels_walker().

find_nonnullable_vars()

List * find_nonnullable_vars

(

Node *

clause

)

Definition at line 1714 of file clauses.c.

{
    return find_nonnullable_vars_walker(clause, true);
}

References find_nonnullable_vars_walker().

Referenced by reduce_outer_joins_pass2().

find_nonnullable_vars_walker()

static List * find_nonnullable_vars_walker ( Node *  node, bool  top_level  )

static

Definition at line 1720 of file clauses.c.

{
    List       *result = NIL;
    ListCell   *l;
 
    if (node == NULL)
        return NIL;
    if (IsA(node, Var))
    {
        Var        *var = (Var *) node;
 
        if (var->varlevelsup == 0)
            result = mbms_add_member(result,
                                     var->varno,
                                     var->varattno - FirstLowInvalidHeapAttributeNumber);
    }
    else if (IsA(node, List))
    {
        /*
         * At top level, we are examining an implicit-AND list: if any of the
         * arms produces FALSE-or-NULL then the result is FALSE-or-NULL. If
         * not at top level, we are examining the arguments of a strict
         * function: if any of them produce NULL then the result of the
         * function must be NULL.  So in both cases, the set of nonnullable
         * vars is the union of those found in the arms, and we pass down the
         * top_level flag unmodified.
         */
        foreach(l, (List *) node)
        {
            result = mbms_add_members(result,
                                      find_nonnullable_vars_walker(lfirst(l),
                                                                   top_level));
        }
    }
    else if (IsA(node, FuncExpr))
    {
        FuncExpr   *expr = (FuncExpr *) node;
 
        if (func_strict(expr->funcid))
            result = find_nonnullable_vars_walker((Node *) expr->args, false);
    }
    else if (IsA(node, OpExpr))
    {
        OpExpr     *expr = (OpExpr *) node;
 
        set_opfuncid(expr);
        if (func_strict(expr->opfuncid))
            result = find_nonnullable_vars_walker((Node *) expr->args, false);
    }
    else if (IsA(node, ScalarArrayOpExpr))
    {
        ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node;
 
        if (is_strict_saop(expr, true))
            result = find_nonnullable_vars_walker((Node *) expr->args, false);
    }
    else if (IsA(node, BoolExpr))
    {
        BoolExpr   *expr = (BoolExpr *) node;
 
        switch (expr->boolop)
        {
            case AND_EXPR:
 
                /*
                 * At top level we can just recurse (to the List case), since
                 * the result should be the union of what we can prove in each
                 * arm.
                 */
                if (top_level)
                {
                    result = find_nonnullable_vars_walker((Node *) expr->args,
                                                          top_level);
                    break;
                }
 
                /*
                 * Below top level, even if one arm produces NULL, the result
                 * could be FALSE (hence not NULL).  However, if *all* the
                 * arms produce NULL then the result is NULL, so we can take
                 * the intersection of the sets of nonnullable vars, just as
                 * for OR.  Fall through to share code.
                 */
                /* FALL THRU */
            case OR_EXPR:
 
                /*
                 * OR is strict if all of its arms are, so we can take the
                 * intersection of the sets of nonnullable vars for each arm.
                 * This works for both values of top_level.
                 */
                foreach(l, expr->args)
                {
                    List       *subresult;
 
                    subresult = find_nonnullable_vars_walker(lfirst(l),
                                                             top_level);
                    if (result == NIL)  /* first subresult? */
                        result = subresult;
                    else
                        result = mbms_int_members(result, subresult);
 
                    /*
                     * If the intersection is empty, we can stop looking. This
                     * also justifies the test for first-subresult above.
                     */
                    if (result == NIL)
                        break;
                }
                break;
            case NOT_EXPR:
                /* NOT will return null if its arg is null */
                result = find_nonnullable_vars_walker((Node *) expr->args,
                                                      false);
                break;
            default:
                elog(ERROR, "unrecognized boolop: %d", (int) expr->boolop);
                break;
        }
    }
    else if (IsA(node, RelabelType))
    {
        RelabelType *expr = (RelabelType *) node;
 
        result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
    }
    else if (IsA(node, CoerceViaIO))
    {
        /* not clear this is useful, but it can't hurt */
        CoerceViaIO *expr = (CoerceViaIO *) node;
 
        result = find_nonnullable_vars_walker((Node *) expr->arg, false);
    }
    else if (IsA(node, ArrayCoerceExpr))
    {
        /* ArrayCoerceExpr is strict at the array level; ignore elemexpr */
        ArrayCoerceExpr *expr = (ArrayCoerceExpr *) node;
 
        result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
    }
    else if (IsA(node, ConvertRowtypeExpr))
    {
        /* not clear this is useful, but it can't hurt */
        ConvertRowtypeExpr *expr = (ConvertRowtypeExpr *) node;
 
        result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
    }
    else if (IsA(node, CollateExpr))
    {
        CollateExpr *expr = (CollateExpr *) node;
 
        result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
    }
    else if (IsA(node, NullTest))
    {
        /* IS NOT NULL can be considered strict, but only at top level */
        NullTest   *expr = (NullTest *) node;
 
        if (top_level && expr->nulltesttype == IS_NOT_NULL && !expr->argisrow)
            result = find_nonnullable_vars_walker((Node *) expr->arg, false);
    }
    else if (IsA(node, BooleanTest))
    {
        /* Boolean tests that reject NULL are strict at top level */
        BooleanTest *expr = (BooleanTest *) node;
 
        if (top_level &&
            (expr->booltesttype == IS_TRUE ||
             expr->booltesttype == IS_FALSE ||
             expr->booltesttype == IS_NOT_UNKNOWN))
            result = find_nonnullable_vars_walker((Node *) expr->arg, false);
    }
    else if (IsA(node, SubPlan))
    {
        SubPlan    *splan = (SubPlan *) node;
 
        /* See analysis in find_nonnullable_rels_walker */
        if ((top_level && splan->subLinkType == ANY_SUBLINK) ||
            splan->subLinkType == ROWCOMPARE_SUBLINK)
            result = find_nonnullable_vars_walker(splan->testexpr, top_level);
    }
    else if (IsA(node, PlaceHolderVar))
    {
        PlaceHolderVar *phv = (PlaceHolderVar *) node;
 
        result = find_nonnullable_vars_walker((Node *) phv->phexpr, top_level);
    }
    return result;
}

References AND_EXPR, ANY_SUBLINK, RelabelType::arg, CoerceViaIO::arg, ArrayCoerceExpr::arg, ConvertRowtypeExpr::arg, CollateExpr::arg, NullTest::arg, BooleanTest::arg, FuncExpr::args, OpExpr::args, ScalarArrayOpExpr::args, BoolExpr::args, BoolExpr::boolop, BooleanTest::booltesttype, elog, ERROR, find_nonnullable_vars_walker(), FirstLowInvalidHeapAttributeNumber, func_strict(), FuncExpr::funcid, IS_FALSE, IS_NOT_NULL, IS_NOT_UNKNOWN, is_strict_saop(), IS_TRUE, IsA, lfirst, mbms_add_member(), mbms_add_members(), mbms_int_members(), NIL, NOT_EXPR, NullTest::nulltesttype, OR_EXPR, ROWCOMPARE_SUBLINK, set_opfuncid(), SubPlan::subLinkType, SubPlan::testexpr, Var::varattno, Var::varlevelsup, and Var::varno.

Referenced by find_nonnullable_vars(), and find_nonnullable_vars_walker().

find_window_functions()

WindowFuncLists * find_window_functions	(	Node *	clause,
		Index	maxWinRef
	)

Definition at line 232 of file clauses.c.

{
    WindowFuncLists *lists = palloc(sizeof(WindowFuncLists));
 
    lists->numWindowFuncs = 0;
    lists->maxWinRef = maxWinRef;
    lists->windowFuncs = (List **) palloc0((maxWinRef + 1) * sizeof(List *));
    (void) find_window_functions_walker(clause, lists);
    return lists;
}

References find_window_functions_walker(), WindowFuncLists::maxWinRef, WindowFuncLists::numWindowFuncs, palloc(), palloc0(), and WindowFuncLists::windowFuncs.

Referenced by grouping_planner().

find_window_functions_walker()

static bool find_window_functions_walker ( Node *  node, WindowFuncLists *  lists  )

static

Definition at line 244 of file clauses.c.

{
    if (node == NULL)
        return false;
    if (IsA(node, WindowFunc))
    {
        WindowFunc *wfunc = (WindowFunc *) node;
 
        /* winref is unsigned, so one-sided test is OK */
        if (wfunc->winref > lists->maxWinRef)
            elog(ERROR, "WindowFunc contains out-of-range winref %u",
                 wfunc->winref);
        /* eliminate duplicates, so that we avoid repeated computation */
        if (!list_member(lists->windowFuncs[wfunc->winref], wfunc))
        {
            lists->windowFuncs[wfunc->winref] =
                lappend(lists->windowFuncs[wfunc->winref], wfunc);
            lists->numWindowFuncs++;
        }
 
        /*
         * We assume that the parser checked that there are no window
         * functions in the arguments or filter clause.  Hence, we need not
         * recurse into them.  (If either the parser or the planner screws up
         * on this point, the executor will still catch it; see ExecInitExpr.)
         */
        return false;
    }
    Assert(!IsA(node, SubLink));
    return expression_tree_walker(node, find_window_functions_walker, lists);
}

References Assert(), elog, ERROR, expression_tree_walker, find_window_functions_walker(), IsA, lappend(), list_member(), WindowFuncLists::maxWinRef, WindowFuncLists::numWindowFuncs, WindowFuncLists::windowFuncs, and WindowFunc::winref.

Referenced by find_window_functions(), and find_window_functions_walker().

inline_function()

static Expr * inline_function ( Oid  funcid, Oid  result_type, Oid  result_collid, Oid  input_collid, List *  args, bool  funcvariadic, HeapTuple  func_tuple, eval_const_expressions_context *  context  )

static

Definition at line 4655 of file clauses.c.

{
    Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
    char       *src;
    Datum       tmp;
    bool        isNull;
    MemoryContext oldcxt;
    MemoryContext mycxt;
    inline_error_callback_arg callback_arg;
    ErrorContextCallback sqlerrcontext;
    FuncExpr   *fexpr;
    SQLFunctionParseInfoPtr pinfo;
    TupleDesc   rettupdesc;
    ParseState *pstate;
    List       *raw_parsetree_list;
    List       *querytree_list;
    Query      *querytree;
    Node       *newexpr;
    int        *usecounts;
    ListCell   *arg;
    int         i;
 
    /*
     * Forget it if the function is not SQL-language or has other showstopper
     * properties.  (The prokind and nargs checks are just paranoia.)
     */
    if (funcform->prolang != SQLlanguageId ||
        funcform->prokind != PROKIND_FUNCTION ||
        funcform->prosecdef ||
        funcform->proretset ||
        funcform->prorettype == RECORDOID ||
        !heap_attisnull(func_tuple, Anum_pg_proc_proconfig, NULL) ||
        funcform->pronargs != list_length(args))
        return NULL;
 
    /* Check for recursive function, and give up trying to expand if so */
    if (list_member_oid(context->active_fns, funcid))
        return NULL;
 
    /* Check permission to call function (fail later, if not) */
    if (object_aclcheck(ProcedureRelationId, funcid, GetUserId(), ACL_EXECUTE) != ACLCHECK_OK)
        return NULL;
 
    /* Check whether a plugin wants to hook function entry/exit */
    if (FmgrHookIsNeeded(funcid))
        return NULL;
 
    /*
     * Make a temporary memory context, so that we don't leak all the stuff
     * that parsing might create.
     */
    mycxt = AllocSetContextCreate(CurrentMemoryContext,
                                  "inline_function",
                                  ALLOCSET_DEFAULT_SIZES);
    oldcxt = MemoryContextSwitchTo(mycxt);
 
    /*
     * We need a dummy FuncExpr node containing the already-simplified
     * arguments.  (In some cases we don't really need it, but building it is
     * cheap enough that it's not worth contortions to avoid.)
     */
    fexpr = makeNode(FuncExpr);
    fexpr->funcid = funcid;
    fexpr->funcresulttype = result_type;
    fexpr->funcretset = false;
    fexpr->funcvariadic = funcvariadic;
    fexpr->funcformat = COERCE_EXPLICIT_CALL;   /* doesn't matter */
    fexpr->funccollid = result_collid;  /* doesn't matter */
    fexpr->inputcollid = input_collid;
    fexpr->args = args;
    fexpr->location = -1;
 
    /* Fetch the function body */
    tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);
    src = TextDatumGetCString(tmp);
 
    /*
     * Setup error traceback support for ereport().  This is so that we can
     * finger the function that bad information came from.
     */
    callback_arg.proname = NameStr(funcform->proname);
    callback_arg.prosrc = src;
 
    sqlerrcontext.callback = sql_inline_error_callback;
    sqlerrcontext.arg = &callback_arg;
    sqlerrcontext.previous = error_context_stack;
    error_context_stack = &sqlerrcontext;
 
    /* If we have prosqlbody, pay attention to that not prosrc */
    tmp = SysCacheGetAttr(PROCOID,
                          func_tuple,
                          Anum_pg_proc_prosqlbody,
                          &isNull);
    if (!isNull)
    {
        Node       *n;
        List       *query_list;
 
        n = stringToNode(TextDatumGetCString(tmp));
        if (IsA(n, List))
            query_list = linitial_node(List, castNode(List, n));
        else
            query_list = list_make1(n);
        if (list_length(query_list) != 1)
            goto fail;
        querytree = linitial(query_list);
 
        /*
         * Because we'll insist below that the querytree have an empty rtable
         * and no sublinks, it cannot have any relation references that need
         * to be locked or rewritten.  So we can omit those steps.
         */
    }
    else
    {
        /* Set up to handle parameters while parsing the function body. */
        pinfo = prepare_sql_fn_parse_info(func_tuple,
                                          (Node *) fexpr,
                                          input_collid);
 
        /*
         * We just do parsing and parse analysis, not rewriting, because
         * rewriting will not affect table-free-SELECT-only queries, which is
         * all that we care about.  Also, we can punt as soon as we detect
         * more than one command in the function body.
         */
        raw_parsetree_list = pg_parse_query(src);
        if (list_length(raw_parsetree_list) != 1)
            goto fail;
 
        pstate = make_parsestate(NULL);
        pstate->p_sourcetext = src;
        sql_fn_parser_setup(pstate, pinfo);
 
        querytree = transformTopLevelStmt(pstate, linitial(raw_parsetree_list));
 
        free_parsestate(pstate);
    }
 
    /*
     * The single command must be a simple "SELECT expression".
     *
     * Note: if you change the tests involved in this, see also plpgsql's
     * exec_simple_check_plan().  That generally needs to have the same idea
     * of what's a "simple expression", so that inlining a function that
     * previously wasn't inlined won't change plpgsql's conclusion.
     */
    if (!IsA(querytree, Query) ||
        querytree->commandType != CMD_SELECT ||
        querytree->hasAggs ||
        querytree->hasWindowFuncs ||
        querytree->hasTargetSRFs ||
        querytree->hasSubLinks ||
        querytree->cteList ||
        querytree->rtable ||
        querytree->jointree->fromlist ||
        querytree->jointree->quals ||
        querytree->groupClause ||
        querytree->groupingSets ||
        querytree->havingQual ||
        querytree->windowClause ||
        querytree->distinctClause ||
        querytree->sortClause ||
        querytree->limitOffset ||
        querytree->limitCount ||
        querytree->setOperations ||
        list_length(querytree->targetList) != 1)
        goto fail;
 
    /* If the function result is composite, resolve it */
    (void) get_expr_result_type((Node *) fexpr,
                                NULL,
                                &rettupdesc);
 
    /*
     * Make sure the function (still) returns what it's declared to.  This
     * will raise an error if wrong, but that's okay since the function would
     * fail at runtime anyway.  Note that check_sql_fn_retval will also insert
     * a coercion if needed to make the tlist expression match the declared
     * type of the function.
     *
     * Note: we do not try this until we have verified that no rewriting was
     * needed; that's probably not important, but let's be careful.
     */
    querytree_list = list_make1(querytree);
    if (check_sql_fn_retval(list_make1(querytree_list),
                            result_type, rettupdesc,
                            funcform->prokind,
                            false))
        goto fail;              /* reject whole-tuple-result cases */
 
    /*
     * Given the tests above, check_sql_fn_retval shouldn't have decided to
     * inject a projection step, but let's just make sure.
     */
    if (querytree != linitial(querytree_list))
        goto fail;
 
    /* Now we can grab the tlist expression */
    newexpr = (Node *) ((TargetEntry *) linitial(querytree->targetList))->expr;
 
    /*
     * If the SQL function returns VOID, we can only inline it if it is a
     * SELECT of an expression returning VOID (ie, it's just a redirection to
     * another VOID-returning function).  In all non-VOID-returning cases,
     * check_sql_fn_retval should ensure that newexpr returns the function's
     * declared result type, so this test shouldn't fail otherwise; but we may
     * as well cope gracefully if it does.
     */
    if (exprType(newexpr) != result_type)
        goto fail;
 
    /*
     * Additional validity checks on the expression.  It mustn't be more
     * volatile than the surrounding function (this is to avoid breaking hacks
     * that involve pretending a function is immutable when it really ain't).
     * If the surrounding function is declared strict, then the expression
     * must contain only strict constructs and must use all of the function
     * parameters (this is overkill, but an exact analysis is hard).
     */
    if (funcform->provolatile == PROVOLATILE_IMMUTABLE &&
        contain_mutable_functions(newexpr))
        goto fail;
    else if (funcform->provolatile == PROVOLATILE_STABLE &&
             contain_volatile_functions(newexpr))
        goto fail;
 
    if (funcform->proisstrict &&
        contain_nonstrict_functions(newexpr))
        goto fail;
 
    /*
     * If any parameter expression contains a context-dependent node, we can't
     * inline, for fear of putting such a node into the wrong context.
     */
    if (contain_context_dependent_node((Node *) args))
        goto fail;
 
    /*
     * We may be able to do it; there are still checks on parameter usage to
     * make, but those are most easily done in combination with the actual
     * substitution of the inputs.  So start building expression with inputs
     * substituted.
     */
    usecounts = (int *) palloc0(funcform->pronargs * sizeof(int));
    newexpr = substitute_actual_parameters(newexpr, funcform->pronargs,
                                           args, usecounts);
 
    /* Now check for parameter usage */
    i = 0;
    foreach(arg, args)
    {
        Node       *param = lfirst(arg);
 
        if (usecounts[i] == 0)
        {
            /* Param not used at all: uncool if func is strict */
            if (funcform->proisstrict)
                goto fail;
        }
        else if (usecounts[i] != 1)
        {
            /* Param used multiple times: uncool if expensive or volatile */
            QualCost    eval_cost;
 
            /*
             * We define "expensive" as "contains any subplan or more than 10
             * operators".  Note that the subplan search has to be done
             * explicitly, since cost_qual_eval() will barf on unplanned
             * subselects.
             */
            if (contain_subplans(param))
                goto fail;
            cost_qual_eval(&eval_cost, list_make1(param), NULL);
            if (eval_cost.startup + eval_cost.per_tuple >
                10 * cpu_operator_cost)
                goto fail;
 
            /*
             * Check volatility last since this is more expensive than the
             * above tests
             */
            if (contain_volatile_functions(param))
                goto fail;
        }
        i++;
    }
 
    /*
     * Whew --- we can make the substitution.  Copy the modified expression
     * out of the temporary memory context, and clean up.
     */
    MemoryContextSwitchTo(oldcxt);
 
    newexpr = copyObject(newexpr);
 
    MemoryContextDelete(mycxt);
 
    /*
     * If the result is of a collatable type, force the result to expose the
     * correct collation.  In most cases this does not matter, but it's
     * possible that the function result is used directly as a sort key or in
     * other places where we expect exprCollation() to tell the truth.
     */
    if (OidIsValid(result_collid))
    {
        Oid         exprcoll = exprCollation(newexpr);
 
        if (OidIsValid(exprcoll) && exprcoll != result_collid)
        {
            CollateExpr *newnode = makeNode(CollateExpr);
 
            newnode->arg = (Expr *) newexpr;
            newnode->collOid = result_collid;
            newnode->location = -1;
 
            newexpr = (Node *) newnode;
        }
    }
 
    /*
     * Since there is now no trace of the function in the plan tree, we must
     * explicitly record the plan's dependency on the function.
     */
    if (context->root)
        record_plan_function_dependency(context->root, funcid);
 
    /*
     * Recursively try to simplify the modified expression.  Here we must add
     * the current function to the context list of active functions.
     */
    context->active_fns = lappend_oid(context->active_fns, funcid);
    newexpr = eval_const_expressions_mutator(newexpr, context);
    context->active_fns = list_delete_last(context->active_fns);
 
    error_context_stack = sqlerrcontext.previous;
 
    return (Expr *) newexpr;
 
    /* Here if func is not inlinable: release temp memory and return NULL */
fail:
    MemoryContextSwitchTo(oldcxt);
    MemoryContextDelete(mycxt);
    error_context_stack = sqlerrcontext.previous;
 
    return NULL;
}

References ACL_EXECUTE, ACLCHECK_OK, eval_const_expressions_context::active_fns, ALLOCSET_DEFAULT_SIZES, AllocSetContextCreate, arg, CollateExpr::arg, ErrorContextCallback::arg, generate_unaccent_rules::args, FuncExpr::args, ErrorContextCallback::callback, castNode, check_sql_fn_retval(), CMD_SELECT, COERCE_EXPLICIT_CALL, CollateExpr::collOid, contain_context_dependent_node(), contain_mutable_functions(), contain_nonstrict_functions(), contain_subplans(), contain_volatile_functions(), copyObject, cost_qual_eval(), cpu_operator_cost, CurrentMemoryContext, error_context_stack, eval_const_expressions_mutator(), exprCollation(), exprType(), FmgrHookIsNeeded, free_parsestate(), FuncExpr::funcid, get_expr_result_type(), GETSTRUCT(), GetUserId(), heap_attisnull(), i, IsA, lappend_oid(), lfirst, linitial, linitial_node, list_delete_last(), list_length(), list_make1, list_member_oid(), FuncExpr::location, CollateExpr::location, make_parsestate(), makeNode, MemoryContextDelete(), MemoryContextSwitchTo(), NameStr, object_aclcheck(), OidIsValid, ParseState::p_sourcetext, palloc0(), QualCost::per_tuple, pg_parse_query(), prepare_sql_fn_parse_info(), ErrorContextCallback::previous, inline_error_callback_arg::proname, inline_error_callback_arg::prosrc, querytree(), record_plan_function_dependency(), eval_const_expressions_context::root, sql_fn_parser_setup(), sql_inline_error_callback(), QualCost::startup, stringToNode(), substitute_actual_parameters(), SysCacheGetAttr(), SysCacheGetAttrNotNull(), TextDatumGetCString, and transformTopLevelStmt().

Referenced by simplify_function().

inline_set_returning_function()

Query * inline_set_returning_function	(	PlannerInfo *	root,
		RangeTblEntry *	rte
	)

Definition at line 5168 of file clauses.c.

{
    RangeTblFunction *rtfunc;
    FuncExpr   *fexpr;
    Oid         func_oid;
    HeapTuple   func_tuple;
    Form_pg_proc funcform;
    char       *src;
    Datum       tmp;
    bool        isNull;
    MemoryContext oldcxt;
    MemoryContext mycxt;
    inline_error_callback_arg callback_arg;
    ErrorContextCallback sqlerrcontext;
    SQLFunctionParseInfoPtr pinfo;
    TypeFuncClass functypclass;
    TupleDesc   rettupdesc;
    List       *raw_parsetree_list;
    List       *querytree_list;
    Query      *querytree;
 
    Assert(rte->rtekind == RTE_FUNCTION);
 
    /*
     * It doesn't make a lot of sense for a SQL SRF to refer to itself in its
     * own FROM clause, since that must cause infinite recursion at runtime.
     * It will cause this code to recurse too, so check for stack overflow.
     * (There's no need to do more.)
     */
    check_stack_depth();
 
    /* Fail if the RTE has ORDINALITY - we don't implement that here. */
    if (rte->funcordinality)
        return NULL;
 
    /* Fail if RTE isn't a single, simple FuncExpr */
    if (list_length(rte->functions) != 1)
        return NULL;
    rtfunc = (RangeTblFunction *) linitial(rte->functions);
 
    if (!IsA(rtfunc->funcexpr, FuncExpr))
        return NULL;
    fexpr = (FuncExpr *) rtfunc->funcexpr;
 
    func_oid = fexpr->funcid;
 
    /*
     * The function must be declared to return a set, else inlining would
     * change the results if the contained SELECT didn't return exactly one
     * row.
     */
    if (!fexpr->funcretset)
        return NULL;
 
    /*
     * Refuse to inline if the arguments contain any volatile functions or
     * sub-selects.  Volatile functions are rejected because inlining may
     * result in the arguments being evaluated multiple times, risking a
     * change in behavior.  Sub-selects are rejected partly for implementation
     * reasons (pushing them down another level might change their behavior)
     * and partly because they're likely to be expensive and so multiple
     * evaluation would be bad.
     */
    if (contain_volatile_functions((Node *) fexpr->args) ||
        contain_subplans((Node *) fexpr->args))
        return NULL;
 
    /* Check permission to call function (fail later, if not) */
    if (object_aclcheck(ProcedureRelationId, func_oid, GetUserId(), ACL_EXECUTE) != ACLCHECK_OK)
        return NULL;
 
    /* Check whether a plugin wants to hook function entry/exit */
    if (FmgrHookIsNeeded(func_oid))
        return NULL;
 
    /*
     * OK, let's take a look at the function's pg_proc entry.
     */
    func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(func_oid));
    if (!HeapTupleIsValid(func_tuple))
        elog(ERROR, "cache lookup failed for function %u", func_oid);
    funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
 
    /*
     * Forget it if the function is not SQL-language or has other showstopper
     * properties.  In particular it mustn't be declared STRICT, since we
     * couldn't enforce that.  It also mustn't be VOLATILE, because that is
     * supposed to cause it to be executed with its own snapshot, rather than
     * sharing the snapshot of the calling query.  We also disallow returning
     * SETOF VOID, because inlining would result in exposing the actual result
     * of the function's last SELECT, which should not happen in that case.
     * (Rechecking prokind, proretset, and pronargs is just paranoia.)
     */
    if (funcform->prolang != SQLlanguageId ||
        funcform->prokind != PROKIND_FUNCTION ||
        funcform->proisstrict ||
        funcform->provolatile == PROVOLATILE_VOLATILE ||
        funcform->prorettype == VOIDOID ||
        funcform->prosecdef ||
        !funcform->proretset ||
        list_length(fexpr->args) != funcform->pronargs ||
        !heap_attisnull(func_tuple, Anum_pg_proc_proconfig, NULL))
    {
        ReleaseSysCache(func_tuple);
        return NULL;
    }
 
    /*
     * Make a temporary memory context, so that we don't leak all the stuff
     * that parsing might create.
     */
    mycxt = AllocSetContextCreate(CurrentMemoryContext,
                                  "inline_set_returning_function",
                                  ALLOCSET_DEFAULT_SIZES);
    oldcxt = MemoryContextSwitchTo(mycxt);
 
    /* Fetch the function body */
    tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);
    src = TextDatumGetCString(tmp);
 
    /*
     * Setup error traceback support for ereport().  This is so that we can
     * finger the function that bad information came from.
     */
    callback_arg.proname = NameStr(funcform->proname);
    callback_arg.prosrc = src;
 
    sqlerrcontext.callback = sql_inline_error_callback;
    sqlerrcontext.arg = &callback_arg;
    sqlerrcontext.previous = error_context_stack;
    error_context_stack = &sqlerrcontext;
 
    /* If we have prosqlbody, pay attention to that not prosrc */
    tmp = SysCacheGetAttr(PROCOID,
                          func_tuple,
                          Anum_pg_proc_prosqlbody,
                          &isNull);
    if (!isNull)
    {
        Node       *n;
 
        n = stringToNode(TextDatumGetCString(tmp));
        if (IsA(n, List))
            querytree_list = linitial_node(List, castNode(List, n));
        else
            querytree_list = list_make1(n);
        if (list_length(querytree_list) != 1)
            goto fail;
        querytree = linitial(querytree_list);
 
        /* Acquire necessary locks, then apply rewriter. */
        AcquireRewriteLocks(querytree, true, false);
        querytree_list = pg_rewrite_query(querytree);
        if (list_length(querytree_list) != 1)
            goto fail;
        querytree = linitial(querytree_list);
    }
    else
    {
        /*
         * Set up to handle parameters while parsing the function body.  We
         * can use the FuncExpr just created as the input for
         * prepare_sql_fn_parse_info.
         */
        pinfo = prepare_sql_fn_parse_info(func_tuple,
                                          (Node *) fexpr,
                                          fexpr->inputcollid);
 
        /*
         * Parse, analyze, and rewrite (unlike inline_function(), we can't
         * skip rewriting here).  We can fail as soon as we find more than one
         * query, though.
         */
        raw_parsetree_list = pg_parse_query(src);
        if (list_length(raw_parsetree_list) != 1)
            goto fail;
 
        querytree_list = pg_analyze_and_rewrite_withcb(linitial(raw_parsetree_list),
                                                       src,
                                                       (ParserSetupHook) sql_fn_parser_setup,
                                                       pinfo, NULL);
        if (list_length(querytree_list) != 1)
            goto fail;
        querytree = linitial(querytree_list);
    }
 
    /*
     * Also resolve the actual function result tupdesc, if composite.  If we
     * have a coldeflist, believe that; otherwise use get_expr_result_type.
     * (This logic should match ExecInitFunctionScan.)
     */
    if (rtfunc->funccolnames != NIL)
    {
        functypclass = TYPEFUNC_RECORD;
        rettupdesc = BuildDescFromLists(rtfunc->funccolnames,
                                        rtfunc->funccoltypes,
                                        rtfunc->funccoltypmods,
                                        rtfunc->funccolcollations);
    }
    else
        functypclass = get_expr_result_type((Node *) fexpr, NULL, &rettupdesc);
 
    /*
     * The single command must be a plain SELECT.
     */
    if (!IsA(querytree, Query) ||
        querytree->commandType != CMD_SELECT)
        goto fail;
 
    /*
     * Make sure the function (still) returns what it's declared to.  This
     * will raise an error if wrong, but that's okay since the function would
     * fail at runtime anyway.  Note that check_sql_fn_retval will also insert
     * coercions if needed to make the tlist expression(s) match the declared
     * type of the function.  We also ask it to insert dummy NULL columns for
     * any dropped columns in rettupdesc, so that the elements of the modified
     * tlist match up to the attribute numbers.
     *
     * If the function returns a composite type, don't inline unless the check
     * shows it's returning a whole tuple result; otherwise what it's
     * returning is a single composite column which is not what we need.
     */
    if (!check_sql_fn_retval(list_make1(querytree_list),
                             fexpr->funcresulttype, rettupdesc,
                             funcform->prokind,
                             true) &&
        (functypclass == TYPEFUNC_COMPOSITE ||
         functypclass == TYPEFUNC_COMPOSITE_DOMAIN ||
         functypclass == TYPEFUNC_RECORD))
        goto fail;              /* reject not-whole-tuple-result cases */
 
    /*
     * check_sql_fn_retval might've inserted a projection step, but that's
     * fine; just make sure we use the upper Query.
     */
    querytree = linitial_node(Query, querytree_list);
 
    /*
     * Looks good --- substitute parameters into the query.
     */
    querytree = substitute_actual_srf_parameters(querytree,
                                                 funcform->pronargs,
                                                 fexpr->args);
 
    /*
     * Copy the modified query out of the temporary memory context, and clean
     * up.
     */
    MemoryContextSwitchTo(oldcxt);
 
    querytree = copyObject(querytree);
 
    MemoryContextDelete(mycxt);
    error_context_stack = sqlerrcontext.previous;
    ReleaseSysCache(func_tuple);
 
    /*
     * We don't have to fix collations here because the upper query is already
     * parsed, ie, the collations in the RTE are what count.
     */
 
    /*
     * Since there is now no trace of the function in the plan tree, we must
     * explicitly record the plan's dependency on the function.
     */
    record_plan_function_dependency(root, func_oid);
 
    /*
     * We must also notice if the inserted query adds a dependency on the
     * calling role due to RLS quals.
     */
    if (querytree->hasRowSecurity)
        root->glob->dependsOnRole = true;
 
    return querytree;
 
    /* Here if func is not inlinable: release temp memory and return NULL */
fail:
    MemoryContextSwitchTo(oldcxt);
    MemoryContextDelete(mycxt);
    error_context_stack = sqlerrcontext.previous;
    ReleaseSysCache(func_tuple);
 
    return NULL;
}

References ACL_EXECUTE, ACLCHECK_OK, AcquireRewriteLocks(), ALLOCSET_DEFAULT_SIZES, AllocSetContextCreate, ErrorContextCallback::arg, FuncExpr::args, Assert(), BuildDescFromLists(), ErrorContextCallback::callback, castNode, check_sql_fn_retval(), check_stack_depth(), CMD_SELECT, contain_subplans(), contain_volatile_functions(), copyObject, CurrentMemoryContext, elog, ERROR, error_context_stack, FmgrHookIsNeeded, RangeTblFunction::funcexpr, FuncExpr::funcid, RangeTblEntry::funcordinality, RangeTblEntry::functions, get_expr_result_type(), GETSTRUCT(), GetUserId(), heap_attisnull(), HeapTupleIsValid, if(), IsA, linitial, linitial_node, list_length(), list_make1, MemoryContextDelete(), MemoryContextSwitchTo(), NameStr, NIL, object_aclcheck(), ObjectIdGetDatum(), pg_analyze_and_rewrite_withcb(), pg_parse_query(), pg_rewrite_query(), prepare_sql_fn_parse_info(), ErrorContextCallback::previous, inline_error_callback_arg::proname, inline_error_callback_arg::prosrc, querytree(), record_plan_function_dependency(), ReleaseSysCache(), root, RTE_FUNCTION, RangeTblEntry::rtekind, SearchSysCache1(), sql_fn_parser_setup(), sql_inline_error_callback(), stringToNode(), substitute_actual_srf_parameters(), SysCacheGetAttr(), SysCacheGetAttrNotNull(), TextDatumGetCString, TYPEFUNC_COMPOSITE, TYPEFUNC_COMPOSITE_DOMAIN, and TYPEFUNC_RECORD.

Referenced by preprocess_function_rtes().

is_parallel_safe()

bool is_parallel_safe	(	PlannerInfo *	root,
		Node *	node
	)

Definition at line 757 of file clauses.c.

{
    max_parallel_hazard_context context;
    PlannerInfo *proot;
    ListCell   *l;
 
    /*
     * Even if the original querytree contained nothing unsafe, we need to
     * search the expression if we have generated any PARAM_EXEC Params while
     * planning, because those are parallel-restricted and there might be one
     * in this expression.  But otherwise we don't need to look.
     */
    if (root->glob->maxParallelHazard == PROPARALLEL_SAFE &&
        root->glob->paramExecTypes == NIL)
        return true;
    /* Else use max_parallel_hazard's search logic, but stop on RESTRICTED */
    context.max_hazard = PROPARALLEL_SAFE;
    context.max_interesting = PROPARALLEL_RESTRICTED;
    context.safe_param_ids = NIL;
 
    /*
     * The params that refer to the same or parent query level are considered
     * parallel-safe.  The idea is that we compute such params at Gather or
     * Gather Merge node and pass their value to workers.
     */
    for (proot = root; proot != NULL; proot = proot->parent_root)
    {
        foreach(l, proot->init_plans)
        {
            SubPlan    *initsubplan = (SubPlan *) lfirst(l);
 
            context.safe_param_ids = list_concat(context.safe_param_ids,
                                                 initsubplan->setParam);
        }
    }
 
    return !max_parallel_hazard_walker(node, &context);
}

References PlannerInfo::init_plans, lfirst, list_concat(), max_parallel_hazard_context::max_hazard, max_parallel_hazard_context::max_interesting, max_parallel_hazard_walker(), NIL, root, max_parallel_hazard_context::safe_param_ids, and SubPlan::setParam.

Referenced by apply_projection_to_path(), build_join_rel(), create_minmaxagg_path(), create_nestloop_plan(), create_partial_unique_paths(), create_projection_path(), create_set_projection_path(), create_window_paths(), find_computable_ec_member(), grouping_planner(), make_grouping_rel(), plan_create_index_workers(), query_planner(), relation_can_be_sorted_early(), and set_rel_consider_parallel().

is_pseudo_constant_clause()

bool is_pseudo_constant_clause

(

Node *

clause

)

Definition at line 2095 of file clauses.c.

{
    /*
     * We could implement this check in one recursive scan.  But since the
     * check for volatile functions is both moderately expensive and unlikely
     * to fail, it seems better to look for Vars first and only check for
     * volatile functions if we find no Vars.
     */
    if (!contain_var_clause(clause) &&
        !contain_volatile_functions(clause))
        return true;
    return false;
}

References contain_var_clause(), and contain_volatile_functions().

Referenced by clauselist_selectivity_ext(), dependency_is_compatible_clause(), dependency_is_compatible_expression(), and find_window_run_conditions().

is_pseudo_constant_clause_relids()

bool is_pseudo_constant_clause_relids	(	Node *	clause,
		Relids	relids
	)

Definition at line 2115 of file clauses.c.

{
    if (bms_is_empty(relids) &&
        !contain_volatile_functions(clause))
        return true;
    return false;
}

References bms_is_empty, and contain_volatile_functions().

Referenced by clauselist_selectivity_ext().

is_strict_saop()

static bool is_strict_saop ( ScalarArrayOpExpr *  expr, bool  falseOK  )

static

Definition at line 2033 of file clauses.c.

{
    Node       *rightop;
 
    /* The contained operator must be strict. */
    set_sa_opfuncid(expr);
    if (!func_strict(expr->opfuncid))
        return false;
    /* If ANY and falseOK, that's all we need to check. */
    if (expr->useOr && falseOK)
        return true;
    /* Else, we have to see if the array is provably non-empty. */
    Assert(list_length(expr->args) == 2);
    rightop = (Node *) lsecond(expr->args);
    if (rightop && IsA(rightop, Const))
    {
        Datum       arraydatum = ((Const *) rightop)->constvalue;
        bool        arrayisnull = ((Const *) rightop)->constisnull;
        ArrayType  *arrayval;
        int         nitems;
 
        if (arrayisnull)
            return false;
        arrayval = DatumGetArrayTypeP(arraydatum);
        nitems = ArrayGetNItems(ARR_NDIM(arrayval), ARR_DIMS(arrayval));
        if (nitems > 0)
            return true;
    }
    else if (rightop && IsA(rightop, ArrayExpr))
    {
        ArrayExpr  *arrayexpr = (ArrayExpr *) rightop;
 
        if (arrayexpr->elements != NIL && !arrayexpr->multidims)
            return true;
    }
    return false;
}

References ScalarArrayOpExpr::args, ARR_DIMS, ARR_NDIM, ArrayGetNItems(), Assert(), DatumGetArrayTypeP, func_strict(), IsA, list_length(), lsecond, NIL, nitems, set_sa_opfuncid(), and ScalarArrayOpExpr::useOr.

Referenced by find_nonnullable_rels_walker(), and find_nonnullable_vars_walker().

make_SAOP_expr()

ScalarArrayOpExpr * make_SAOP_expr	(	Oid	oper,
		Node *	leftexpr,
		Oid	coltype,
		Oid	arraycollid,
		Oid	inputcollid,
		List *	exprs,
		bool	haveNonConst
	)

Definition at line 5553 of file clauses.c.

{
    Node       *arrayNode = NULL;
    ScalarArrayOpExpr *saopexpr = NULL;
    Oid         arraytype = get_array_type(coltype);
 
    if (!OidIsValid(arraytype))
        return NULL;
 
    /*
     * Assemble an array from the list of constants.  It seems more profitable
     * to build a const array.  But in the presence of other nodes, we don't
     * have a specific value here and must employ an ArrayExpr instead.
     */
    if (haveNonConst)
    {
        ArrayExpr  *arrayExpr = makeNode(ArrayExpr);
 
        /* array_collid will be set by parse_collate.c */
        arrayExpr->element_typeid = coltype;
        arrayExpr->array_typeid = arraytype;
        arrayExpr->multidims = false;
        arrayExpr->elements = exprs;
        arrayExpr->location = -1;
 
        arrayNode = (Node *) arrayExpr;
    }
    else
    {
        int16       typlen;
        bool        typbyval;
        char        typalign;
        Datum      *elems;
        bool       *nulls;
        int         i = 0;
        ArrayType  *arrayConst;
        int         dims[1] = {list_length(exprs)};
        int         lbs[1] = {1};
 
        get_typlenbyvalalign(coltype, &typlen, &typbyval, &typalign);
 
        elems = (Datum *) palloc(sizeof(Datum) * list_length(exprs));
        nulls = (bool *) palloc(sizeof(bool) * list_length(exprs));
        foreach_node(Const, value, exprs)
        {
            elems[i] = value->constvalue;
            nulls[i++] = value->constisnull;
        }
 
        arrayConst = construct_md_array(elems, nulls, 1, dims, lbs,
                                        coltype, typlen, typbyval, typalign);
        arrayNode = (Node *) makeConst(arraytype, -1, arraycollid,
                                       -1, PointerGetDatum(arrayConst),
                                       false, false);
 
        pfree(elems);
        pfree(nulls);
        list_free(exprs);
    }
 
    /* Build the SAOP expression node */
    saopexpr = makeNode(ScalarArrayOpExpr);
    saopexpr->opno = oper;
    saopexpr->opfuncid = get_opcode(oper);
    saopexpr->hashfuncid = InvalidOid;
    saopexpr->negfuncid = InvalidOid;
    saopexpr->useOr = true;
    saopexpr->inputcollid = inputcollid;
    saopexpr->args = list_make2(leftexpr, arrayNode);
    saopexpr->location = -1;
 
    return saopexpr;
}

References ScalarArrayOpExpr::args, construct_md_array(), foreach_node, get_array_type(), get_opcode(), get_typlenbyvalalign(), i, InvalidOid, list_free(), list_length(), list_make2, ScalarArrayOpExpr::location, ArrayExpr::location, makeConst(), makeNode, OidIsValid, oper(), ScalarArrayOpExpr::opno, palloc(), pfree(), PointerGetDatum(), typalign, ScalarArrayOpExpr::useOr, and value.

Referenced by convert_VALUES_to_ANY(), and match_orclause_to_indexcol().

max_parallel_hazard()

char max_parallel_hazard

(

Query *

parse

)

Definition at line 738 of file clauses.c.

{
    max_parallel_hazard_context context;
 
    context.max_hazard = PROPARALLEL_SAFE;
    context.max_interesting = PROPARALLEL_UNSAFE;
    context.safe_param_ids = NIL;
    (void) max_parallel_hazard_walker((Node *) parse, &context);
    return context.max_hazard;
}

References max_parallel_hazard_context::max_hazard, max_parallel_hazard_context::max_interesting, max_parallel_hazard_walker(), NIL, parse(), and max_parallel_hazard_context::safe_param_ids.

Referenced by standard_planner().

max_parallel_hazard_checker()

static bool max_parallel_hazard_checker ( Oid  func_id, void *  context  )

static

Definition at line 826 of file clauses.c.

{
    return max_parallel_hazard_test(func_parallel(func_id),
                                    (max_parallel_hazard_context *) context);
}

References func_parallel(), and max_parallel_hazard_test().

Referenced by max_parallel_hazard_walker().

max_parallel_hazard_test()

static bool max_parallel_hazard_test ( char  proparallel, max_parallel_hazard_context *  context  )

static

Definition at line 798 of file clauses.c.

{
    switch (proparallel)
    {
        case PROPARALLEL_SAFE:
            /* nothing to see here, move along */
            break;
        case PROPARALLEL_RESTRICTED:
            /* increase max_hazard to RESTRICTED */
            Assert(context->max_hazard != PROPARALLEL_UNSAFE);
            context->max_hazard = proparallel;
            /* done if we are not expecting any unsafe functions */
            if (context->max_interesting == proparallel)
                return true;
            break;
        case PROPARALLEL_UNSAFE:
            context->max_hazard = proparallel;
            /* we're always done at the first unsafe construct */
            return true;
        default:
            elog(ERROR, "unrecognized proparallel value \"%c\"", proparallel);
            break;
    }
    return false;
}

References Assert(), elog, ERROR, max_parallel_hazard_context::max_hazard, and max_parallel_hazard_context::max_interesting.

Referenced by max_parallel_hazard_checker(), and max_parallel_hazard_walker().

max_parallel_hazard_walker()

static bool max_parallel_hazard_walker ( Node *  node, max_parallel_hazard_context *  context  )

static

Definition at line 833 of file clauses.c.

{
    if (node == NULL)
        return false;
 
    /* Check for hazardous functions in node itself */
    if (check_functions_in_node(node, max_parallel_hazard_checker,
                                context))
        return true;
 
    /*
     * It should be OK to treat MinMaxExpr as parallel-safe, since btree
     * opclass support functions are generally parallel-safe.  XmlExpr is a
     * bit more dubious but we can probably get away with it.  We err on the
     * side of caution by treating CoerceToDomain as parallel-restricted.
     * (Note: in principle that's wrong because a domain constraint could
     * contain a parallel-unsafe function; but useful constraints probably
     * never would have such, and assuming they do would cripple use of
     * parallel query in the presence of domain types.)  SQLValueFunction
     * should be safe in all cases.  NextValueExpr is parallel-unsafe.
     */
    if (IsA(node, CoerceToDomain))
    {
        if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
            return true;
    }
 
    else if (IsA(node, NextValueExpr))
    {
        if (max_parallel_hazard_test(PROPARALLEL_UNSAFE, context))
            return true;
    }
 
    /*
     * Treat window functions as parallel-restricted because we aren't sure
     * whether the input row ordering is fully deterministic, and the output
     * of window functions might vary across workers if not.  (In some cases,
     * like where the window frame orders by a primary key, we could relax
     * this restriction.  But it doesn't currently seem worth expending extra
     * effort to do so.)
     */
    else if (IsA(node, WindowFunc))
    {
        if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
            return true;
    }
 
    /*
     * As a notational convenience for callers, look through RestrictInfo.
     */
    else if (IsA(node, RestrictInfo))
    {
        RestrictInfo *rinfo = (RestrictInfo *) node;
 
        return max_parallel_hazard_walker((Node *) rinfo->clause, context);
    }
 
    /*
     * Really we should not see SubLink during a max_interesting == restricted
     * scan, but if we do, return true.
     */
    else if (IsA(node, SubLink))
    {
        if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
            return true;
    }
 
    /*
     * Only parallel-safe SubPlans can be sent to workers.  Within the
     * testexpr of the SubPlan, Params representing the output columns of the
     * subplan can be treated as parallel-safe, so temporarily add their IDs
     * to the safe_param_ids list while examining the testexpr.
     */
    else if (IsA(node, SubPlan))
    {
        SubPlan    *subplan = (SubPlan *) node;
        List       *save_safe_param_ids;
 
        if (!subplan->parallel_safe &&
            max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
            return true;
        save_safe_param_ids = context->safe_param_ids;
        context->safe_param_ids = list_concat_copy(context->safe_param_ids,
                                                   subplan->paramIds);
        if (max_parallel_hazard_walker(subplan->testexpr, context))
            return true;        /* no need to restore safe_param_ids */
        list_free(context->safe_param_ids);
        context->safe_param_ids = save_safe_param_ids;
        /* we must also check args, but no special Param treatment there */
        if (max_parallel_hazard_walker((Node *) subplan->args, context))
            return true;
        /* don't want to recurse normally, so we're done */
        return false;
    }
 
    /*
     * We can't pass Params to workers at the moment either, so they are also
     * parallel-restricted, unless they are PARAM_EXTERN Params or are
     * PARAM_EXEC Params listed in safe_param_ids, meaning they could be
     * either generated within workers or can be computed by the leader and
     * then their value can be passed to workers.
     */
    else if (IsA(node, Param))
    {
        Param      *param = (Param *) node;
 
        if (param->paramkind == PARAM_EXTERN)
            return false;
 
        if (param->paramkind != PARAM_EXEC ||
            !list_member_int(context->safe_param_ids, param->paramid))
        {
            if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
                return true;
        }
        return false;           /* nothing to recurse to */
    }
 
    /*
     * When we're first invoked on a completely unplanned tree, we must
     * recurse into subqueries so to as to locate parallel-unsafe constructs
     * anywhere in the tree.
     */
    else if (IsA(node, Query))
    {
        Query      *query = (Query *) node;
 
        /* SELECT FOR UPDATE/SHARE must be treated as unsafe */
        if (query->rowMarks != NULL)
        {
            context->max_hazard = PROPARALLEL_UNSAFE;
            return true;
        }
 
        /* Recurse into subselects */
        return query_tree_walker(query,
                                 max_parallel_hazard_walker,
                                 context, 0);
    }
 
    /* Recurse to check arguments */
    return expression_tree_walker(node,
                                  max_parallel_hazard_walker,
                                  context);
}

References SubPlan::args, check_functions_in_node(), RestrictInfo::clause, expression_tree_walker, IsA, list_concat_copy(), list_free(), list_member_int(), max_parallel_hazard_context::max_hazard, max_parallel_hazard_checker(), max_parallel_hazard_test(), max_parallel_hazard_walker(), SubPlan::parallel_safe, PARAM_EXEC, PARAM_EXTERN, Param::paramid, SubPlan::paramIds, Param::paramkind, query_tree_walker, Query::rowMarks, max_parallel_hazard_context::safe_param_ids, and SubPlan::testexpr.

Referenced by is_parallel_safe(), max_parallel_hazard(), and max_parallel_hazard_walker().

NumRelids()

int NumRelids	(	PlannerInfo *	root,
		Node *	clause
	)

Definition at line 2137 of file clauses.c.

{
    int         result;
    Relids      varnos = pull_varnos(root, clause);
 
    varnos = bms_del_members(varnos, root->outer_join_rels);
    result = bms_num_members(varnos);
    bms_free(varnos);
    return result;
}

References bms_del_members(), bms_free(), bms_num_members(), pull_varnos(), and root.

Referenced by clauselist_selectivity_ext(), rowcomparesel(), and treat_as_join_clause().

pull_paramids()

Bitmapset * pull_paramids

(

Expr *

expr

)

Definition at line 5521 of file clauses.c.

{
    Bitmapset  *result = NULL;
 
    (void) pull_paramids_walker((Node *) expr, &result);
 
    return result;
}

References pull_paramids_walker().

Referenced by create_memoize_plan().

pull_paramids_walker()

static bool pull_paramids_walker ( Node *  node, Bitmapset **  context  )

static

Definition at line 5531 of file clauses.c.

{
    if (node == NULL)
        return false;
    if (IsA(node, Param))
    {
        Param      *param = (Param *) node;
 
        *context = bms_add_member(*context, param->paramid);
        return false;
    }
    return expression_tree_walker(node, pull_paramids_walker, context);
}

References bms_add_member(), expression_tree_walker, IsA, Param::paramid, and pull_paramids_walker().

Referenced by pull_paramids(), and pull_paramids_walker().

recheck_cast_function_args()

static void recheck_cast_function_args ( List *  args, Oid  result_type, Oid *  proargtypes, int  pronargs, HeapTuple  func_tuple  )

static

Definition at line 4484 of file clauses.c.

{
    Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
    int         nargs;
    Oid         actual_arg_types[FUNC_MAX_ARGS];
    Oid         declared_arg_types[FUNC_MAX_ARGS];
    Oid         rettype;
    ListCell   *lc;
 
    if (list_length(args) > FUNC_MAX_ARGS)
        elog(ERROR, "too many function arguments");
    nargs = 0;
    foreach(lc, args)
    {
        actual_arg_types[nargs++] = exprType((Node *) lfirst(lc));
    }
    Assert(nargs == pronargs);
    memcpy(declared_arg_types, proargtypes, pronargs * sizeof(Oid));
    rettype = enforce_generic_type_consistency(actual_arg_types,
                                               declared_arg_types,
                                               nargs,
                                               funcform->prorettype,
                                               false);
    /* let's just check we got the same answer as the parser did ... */
    if (rettype != result_type)
        elog(ERROR, "function's resolved result type changed during planning");
 
    /* perform any necessary typecasting of arguments */
    make_fn_arguments(NULL, args, actual_arg_types, declared_arg_types);
}

References generate_unaccent_rules::args, Assert(), elog, enforce_generic_type_consistency(), ERROR, exprType(), FUNC_MAX_ARGS, GETSTRUCT(), lfirst, list_length(), make_fn_arguments(), and pronargs.

Referenced by expand_function_arguments().

reorder_function_arguments()

static List * reorder_function_arguments ( List *  args, int  pronargs, HeapTuple  func_tuple  )

static

Definition at line 4360 of file clauses.c.

{
    Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
    int         nargsprovided = list_length(args);
    Node       *argarray[FUNC_MAX_ARGS];
    ListCell   *lc;
    int         i;
 
    Assert(nargsprovided <= pronargs);
    if (pronargs < 0 || pronargs > FUNC_MAX_ARGS)
        elog(ERROR, "too many function arguments");
    memset(argarray, 0, pronargs * sizeof(Node *));
 
    /* Deconstruct the argument list into an array indexed by argnumber */
    i = 0;
    foreach(lc, args)
    {
        Node       *arg = (Node *) lfirst(lc);
 
        if (!IsA(arg, NamedArgExpr))
        {
            /* positional argument, assumed to precede all named args */
            Assert(argarray[i] == NULL);
            argarray[i++] = arg;
        }
        else
        {
            NamedArgExpr *na = (NamedArgExpr *) arg;
 
            Assert(na->argnumber >= 0 && na->argnumber < pronargs);
            Assert(argarray[na->argnumber] == NULL);
            argarray[na->argnumber] = (Node *) na->arg;
        }
    }
 
    /*
     * Fetch default expressions, if needed, and insert into array at proper
     * locations (they aren't necessarily consecutive or all used)
     */
    if (nargsprovided < pronargs)
    {
        List       *defaults = fetch_function_defaults(func_tuple);
 
        i = pronargs - funcform->pronargdefaults;
        foreach(lc, defaults)
        {
            if (argarray[i] == NULL)
                argarray[i] = (Node *) lfirst(lc);
            i++;
        }
    }
 
    /* Now reconstruct the args list in proper order */
    args = NIL;
    for (i = 0; i < pronargs; i++)
    {
        Assert(argarray[i] != NULL);
        args = lappend(args, argarray[i]);
    }
 
    return args;
}

References arg, NamedArgExpr::arg, NamedArgExpr::argnumber, generate_unaccent_rules::args, Assert(), elog, ERROR, fetch_function_defaults(), FUNC_MAX_ARGS, GETSTRUCT(), i, IsA, lappend(), lfirst, list_length(), NIL, and pronargs.

Referenced by expand_function_arguments().

rowtype_field_matches()

static bool rowtype_field_matches ( Oid  rowtypeid, int  fieldnum, Oid  expectedtype, int32  expectedtypmod, Oid  expectedcollation  )

static

Definition at line 2193 of file clauses.c.

{
    TupleDesc   tupdesc;
    Form_pg_attribute attr;
 
    /* No issue for RECORD, since there is no way to ALTER such a type */
    if (rowtypeid == RECORDOID)
        return true;
    tupdesc = lookup_rowtype_tupdesc_domain(rowtypeid, -1, false);
    if (fieldnum <= 0 || fieldnum > tupdesc->natts)
    {
        ReleaseTupleDesc(tupdesc);
        return false;
    }
    attr = TupleDescAttr(tupdesc, fieldnum - 1);
    if (attr->attisdropped ||
        attr->atttypid != expectedtype ||
        attr->atttypmod != expectedtypmod ||
        attr->attcollation != expectedcollation)
    {
        ReleaseTupleDesc(tupdesc);
        return false;
    }
    ReleaseTupleDesc(tupdesc);
    return true;
}

References lookup_rowtype_tupdesc_domain(), TupleDescData::natts, ReleaseTupleDesc, and TupleDescAttr().

Referenced by eval_const_expressions_mutator().

simplify_and_arguments()

static List * simplify_and_arguments ( List *  args, eval_const_expressions_context *  context, bool *  haveNull, bool *  forceFalse  )

static

Definition at line 3939 of file clauses.c.

{
    List       *newargs = NIL;
    List       *unprocessed_args;
 
    /* See comments in simplify_or_arguments */
    unprocessed_args = list_copy(args);
    while (unprocessed_args)
    {
        Node       *arg = (Node *) linitial(unprocessed_args);
 
        unprocessed_args = list_delete_first(unprocessed_args);
 
        /* flatten nested ANDs as per above comment */
        if (is_andclause(arg))
        {
            List       *subargs = ((BoolExpr *) arg)->args;
            List       *oldlist = unprocessed_args;
 
            unprocessed_args = list_concat_copy(subargs, unprocessed_args);
            /* perhaps-overly-tense code to avoid leaking old lists */
            list_free(oldlist);
            continue;
        }
 
        /* If it's not an AND, simplify it */
        arg = eval_const_expressions_mutator(arg, context);
 
        /*
         * It is unlikely but not impossible for simplification of a non-AND
         * clause to produce an AND.  Recheck, but don't be too tense about it
         * since it's not a mainstream case.  In particular we don't worry
         * about const-simplifying the input twice, nor about list leakage.
         */
        if (is_andclause(arg))
        {
            List       *subargs = ((BoolExpr *) arg)->args;
 
            unprocessed_args = list_concat_copy(subargs, unprocessed_args);
            continue;
        }
 
        /*
         * OK, we have a const-simplified non-AND argument.  Process it per
         * comments above.
         */
        if (IsA(arg, Const))
        {
            Const      *const_input = (Const *) arg;
 
            if (const_input->constisnull)
                *haveNull = true;
            else if (!DatumGetBool(const_input->constvalue))
            {
                *forceFalse = true;
 
                /*
                 * Once we detect a FALSE result we can just exit the loop
                 * immediately.  However, if we ever add a notion of
                 * non-removable functions, we'd need to keep scanning.
                 */
                return NIL;
            }
            /* otherwise, we can drop the constant-true input */
            continue;
        }
 
        /* else emit the simplified arg into the result list */
        newargs = lappend(newargs, arg);
    }
 
    return newargs;
}

References arg, generate_unaccent_rules::args, DatumGetBool(), eval_const_expressions_mutator(), is_andclause(), IsA, lappend(), linitial, list_concat_copy(), list_copy(), list_delete_first(), list_free(), and NIL.

Referenced by eval_const_expressions_mutator().

simplify_boolean_equality()

static Node * simplify_boolean_equality ( Oid  opno, List *  args  )

static

Definition at line 4033 of file clauses.c.

{
    Node       *leftop;
    Node       *rightop;
 
    Assert(list_length(args) == 2);
    leftop = linitial(args);
    rightop = lsecond(args);
    if (leftop && IsA(leftop, Const))
    {
        Assert(!((Const *) leftop)->constisnull);
        if (opno == BooleanEqualOperator)
        {
            if (DatumGetBool(((Const *) leftop)->constvalue))
                return rightop; /* true = foo */
            else
                return negate_clause(rightop);  /* false = foo */
        }
        else
        {
            if (DatumGetBool(((Const *) leftop)->constvalue))
                return negate_clause(rightop);  /* true <> foo */
            else
                return rightop; /* false <> foo */
        }
    }
    if (rightop && IsA(rightop, Const))
    {
        Assert(!((Const *) rightop)->constisnull);
        if (opno == BooleanEqualOperator)
        {
            if (DatumGetBool(((Const *) rightop)->constvalue))
                return leftop;  /* foo = true */
            else
                return negate_clause(leftop);   /* foo = false */
        }
        else
        {
            if (DatumGetBool(((Const *) rightop)->constvalue))
                return negate_clause(leftop);   /* foo <> true */
            else
                return leftop;  /* foo <> false */
        }
    }
    return NULL;
}

References generate_unaccent_rules::args, Assert(), DatumGetBool(), IsA, linitial, list_length(), lsecond, and negate_clause().

Referenced by eval_const_expressions_mutator().

simplify_function()

static Expr * simplify_function ( Oid  funcid, Oid  result_type, int32  result_typmod, Oid  result_collid, Oid  input_collid, List **  args_p, bool  funcvariadic, bool  process_args, bool  allow_non_const, eval_const_expressions_context *  context  )

static

Definition at line 4102 of file clauses.c.

{
    List       *args = *args_p;
    HeapTuple   func_tuple;
    Form_pg_proc func_form;
    Expr       *newexpr;
 
    /*
     * We have three strategies for simplification: execute the function to
     * deliver a constant result, use a transform function to generate a
     * substitute node tree, or expand in-line the body of the function
     * definition (which only works for simple SQL-language functions, but
     * that is a common case).  Each case needs access to the function's
     * pg_proc tuple, so fetch it just once.
     *
     * Note: the allow_non_const flag suppresses both the second and third
     * strategies; so if !allow_non_const, simplify_function can only return a
     * Const or NULL.  Argument-list rewriting happens anyway, though.
     */
    func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
    if (!HeapTupleIsValid(func_tuple))
        elog(ERROR, "cache lookup failed for function %u", funcid);
    func_form = (Form_pg_proc) GETSTRUCT(func_tuple);
 
    /*
     * Process the function arguments, unless the caller did it already.
     *
     * Here we must deal with named or defaulted arguments, and then
     * recursively apply eval_const_expressions to the whole argument list.
     */
    if (process_args)
    {
        args = expand_function_arguments(args, false, result_type, func_tuple);
        args = (List *) expression_tree_mutator((Node *) args,
                                                eval_const_expressions_mutator,
                                                context);
        /* Argument processing done, give it back to the caller */
        *args_p = args;
    }
 
    /* Now attempt simplification of the function call proper. */
 
    newexpr = evaluate_function(funcid, result_type, result_typmod,
                                result_collid, input_collid,
                                args, funcvariadic,
                                func_tuple, context);
 
    if (!newexpr && allow_non_const && OidIsValid(func_form->prosupport))
    {
        /*
         * Build a SupportRequestSimplify node to pass to the support
         * function, pointing to a dummy FuncExpr node containing the
         * simplified arg list.  We use this approach to present a uniform
         * interface to the support function regardless of how the target
         * function is actually being invoked.
         */
        SupportRequestSimplify req;
        FuncExpr    fexpr;
 
        fexpr.xpr.type = T_FuncExpr;
        fexpr.funcid = funcid;
        fexpr.funcresulttype = result_type;
        fexpr.funcretset = func_form->proretset;
        fexpr.funcvariadic = funcvariadic;
        fexpr.funcformat = COERCE_EXPLICIT_CALL;
        fexpr.funccollid = result_collid;
        fexpr.inputcollid = input_collid;
        fexpr.args = args;
        fexpr.location = -1;
 
        req.type = T_SupportRequestSimplify;
        req.root = context->root;
        req.fcall = &fexpr;
 
        newexpr = (Expr *)
            DatumGetPointer(OidFunctionCall1(func_form->prosupport,
                                             PointerGetDatum(&req)));
 
        /* catch a possible API misunderstanding */
        Assert(newexpr != (Expr *) &fexpr);
    }
 
    if (!newexpr && allow_non_const)
        newexpr = inline_function(funcid, result_type, result_collid,
                                  input_collid, args, funcvariadic,
                                  func_tuple, context);
 
    ReleaseSysCache(func_tuple);
 
    return newexpr;
}

References generate_unaccent_rules::args, FuncExpr::args, Assert(), COERCE_EXPLICIT_CALL, DatumGetPointer(), elog, ERROR, eval_const_expressions_mutator(), evaluate_function(), expand_function_arguments(), expression_tree_mutator, SupportRequestSimplify::fcall, FuncExpr::funcid, GETSTRUCT(), HeapTupleIsValid, inline_function(), FuncExpr::location, ObjectIdGetDatum(), OidFunctionCall1, OidIsValid, PointerGetDatum(), ReleaseSysCache(), eval_const_expressions_context::root, SupportRequestSimplify::root, SearchSysCache1(), SupportRequestSimplify::type, and FuncExpr::xpr.

Referenced by eval_const_expressions_mutator().

simplify_or_arguments()

static List * simplify_or_arguments ( List *  args, eval_const_expressions_context *  context, bool *  haveNull, bool *  forceTrue  )

static

Definition at line 3833 of file clauses.c.

{
    List       *newargs = NIL;
    List       *unprocessed_args;
 
    /*
     * We want to ensure that any OR immediately beneath another OR gets
     * flattened into a single OR-list, so as to simplify later reasoning.
     *
     * To avoid stack overflow from recursion of eval_const_expressions, we
     * resort to some tenseness here: we keep a list of not-yet-processed
     * inputs, and handle flattening of nested ORs by prepending to the to-do
     * list instead of recursing.  Now that the parser generates N-argument
     * ORs from simple lists, this complexity is probably less necessary than
     * it once was, but we might as well keep the logic.
     */
    unprocessed_args = list_copy(args);
    while (unprocessed_args)
    {
        Node       *arg = (Node *) linitial(unprocessed_args);
 
        unprocessed_args = list_delete_first(unprocessed_args);
 
        /* flatten nested ORs as per above comment */
        if (is_orclause(arg))
        {
            List       *subargs = ((BoolExpr *) arg)->args;
            List       *oldlist = unprocessed_args;
 
            unprocessed_args = list_concat_copy(subargs, unprocessed_args);
            /* perhaps-overly-tense code to avoid leaking old lists */
            list_free(oldlist);
            continue;
        }
 
        /* If it's not an OR, simplify it */
        arg = eval_const_expressions_mutator(arg, context);
 
        /*
         * It is unlikely but not impossible for simplification of a non-OR
         * clause to produce an OR.  Recheck, but don't be too tense about it
         * since it's not a mainstream case.  In particular we don't worry
         * about const-simplifying the input twice, nor about list leakage.
         */
        if (is_orclause(arg))
        {
            List       *subargs = ((BoolExpr *) arg)->args;
 
            unprocessed_args = list_concat_copy(subargs, unprocessed_args);
            continue;
        }
 
        /*
         * OK, we have a const-simplified non-OR argument.  Process it per
         * comments above.
         */
        if (IsA(arg, Const))
        {
            Const      *const_input = (Const *) arg;
 
            if (const_input->constisnull)
                *haveNull = true;
            else if (DatumGetBool(const_input->constvalue))
            {
                *forceTrue = true;
 
                /*
                 * Once we detect a TRUE result we can just exit the loop
                 * immediately.  However, if we ever add a notion of
                 * non-removable functions, we'd need to keep scanning.
                 */
                return NIL;
            }
            /* otherwise, we can drop the constant-false input */
            continue;
        }
 
        /* else emit the simplified arg into the result list */
        newargs = lappend(newargs, arg);
    }
 
    return newargs;
}

References arg, generate_unaccent_rules::args, DatumGetBool(), eval_const_expressions_mutator(), is_orclause(), IsA, lappend(), linitial, list_concat_copy(), list_copy(), list_delete_first(), list_free(), and NIL.

Referenced by eval_const_expressions_mutator().

sql_inline_error_callback()

static void sql_inline_error_callback ( void *  arg )

static

Definition at line 5052 of file clauses.c.

{
    inline_error_callback_arg *callback_arg = (inline_error_callback_arg *) arg;
    int         syntaxerrposition;
 
    /* If it's a syntax error, convert to internal syntax error report */
    syntaxerrposition = geterrposition();
    if (syntaxerrposition > 0)
    {
        errposition(0);
        internalerrposition(syntaxerrposition);
        internalerrquery(callback_arg->prosrc);
    }
 
    errcontext("SQL function \"%s\" during inlining", callback_arg->proname);
}

References arg, errcontext, errposition(), geterrposition(), internalerrposition(), internalerrquery(), inline_error_callback_arg::proname, and inline_error_callback_arg::prosrc.

Referenced by inline_function(), and inline_set_returning_function().

substitute_actual_parameters()

static Node * substitute_actual_parameters ( Node *  expr, int  nargs, List *  args, int *  usecounts  )

static

Definition at line 5011 of file clauses.c.

{
    substitute_actual_parameters_context context;
 
    context.nargs = nargs;
    context.args = args;
    context.usecounts = usecounts;
 
    return substitute_actual_parameters_mutator(expr, &context);
}

References generate_unaccent_rules::args, substitute_actual_parameters_context::args, substitute_actual_parameters_context::nargs, substitute_actual_parameters_mutator(), and substitute_actual_parameters_context::usecounts.

Referenced by inline_function().

substitute_actual_parameters_mutator()

static Node * substitute_actual_parameters_mutator ( Node *  node, substitute_actual_parameters_context *  context  )

static

Definition at line 5024 of file clauses.c.

{
    if (node == NULL)
        return NULL;
    if (IsA(node, Param))
    {
        Param      *param = (Param *) node;
 
        if (param->paramkind != PARAM_EXTERN)
            elog(ERROR, "unexpected paramkind: %d", (int) param->paramkind);
        if (param->paramid <= 0 || param->paramid > context->nargs)
            elog(ERROR, "invalid paramid: %d", param->paramid);
 
        /* Count usage of parameter */
        context->usecounts[param->paramid - 1]++;
 
        /* Select the appropriate actual arg and replace the Param with it */
        /* We don't need to copy at this time (it'll get done later) */
        return list_nth(context->args, param->paramid - 1);
    }
    return expression_tree_mutator(node, substitute_actual_parameters_mutator, context);
}

References substitute_actual_parameters_context::args, elog, ERROR, expression_tree_mutator, IsA, list_nth(), substitute_actual_parameters_context::nargs, PARAM_EXTERN, Param::paramid, Param::paramkind, substitute_actual_parameters_mutator(), and substitute_actual_parameters_context::usecounts.

Referenced by substitute_actual_parameters(), and substitute_actual_parameters_mutator().

substitute_actual_srf_parameters()

static Query * substitute_actual_srf_parameters ( Query *  expr, int  nargs, List *  args  )

static

Definition at line 5461 of file clauses.c.

{
    substitute_actual_srf_parameters_context context;
 
    context.nargs = nargs;
    context.args = args;
    context.sublevels_up = 1;
 
    return query_tree_mutator(expr,
                              substitute_actual_srf_parameters_mutator,
                              &context,
                              0);
}

References generate_unaccent_rules::args, substitute_actual_srf_parameters_context::args, substitute_actual_srf_parameters_context::nargs, query_tree_mutator, substitute_actual_srf_parameters_context::sublevels_up, and substitute_actual_srf_parameters_mutator().

Referenced by inline_set_returning_function().

substitute_actual_srf_parameters_mutator()

static Node * substitute_actual_srf_parameters_mutator ( Node *  node, substitute_actual_srf_parameters_context *  context  )

static

Definition at line 5476 of file clauses.c.

{
    Node       *result;
 
    if (node == NULL)
        return NULL;
    if (IsA(node, Query))
    {
        context->sublevels_up++;
        result = (Node *) query_tree_mutator((Query *) node,
                                             substitute_actual_srf_parameters_mutator,
                                             context,
                                             0);
        context->sublevels_up--;
        return result;
    }
    if (IsA(node, Param))
    {
        Param      *param = (Param *) node;
 
        if (param->paramkind == PARAM_EXTERN)
        {
            if (param->paramid <= 0 || param->paramid > context->nargs)
                elog(ERROR, "invalid paramid: %d", param->paramid);
 
            /*
             * Since the parameter is being inserted into a subquery, we must
             * adjust levels.
             */
            result = copyObject(list_nth(context->args, param->paramid - 1));
            IncrementVarSublevelsUp(result, context->sublevels_up, 0);
            return result;
        }
    }
    return expression_tree_mutator(node,
                                   substitute_actual_srf_parameters_mutator,
                                   context);
}

References substitute_actual_srf_parameters_context::args, copyObject, elog, ERROR, expression_tree_mutator, IncrementVarSublevelsUp(), IsA, list_nth(), substitute_actual_srf_parameters_context::nargs, PARAM_EXTERN, Param::paramid, Param::paramkind, query_tree_mutator, substitute_actual_srf_parameters_context::sublevels_up, and substitute_actual_srf_parameters_mutator().

Referenced by substitute_actual_srf_parameters(), and substitute_actual_srf_parameters_mutator().

var_is_nonnullable()

bool var_is_nonnullable	(	PlannerInfo *	root,
		Var *	var,
		bool	use_rel_info
	)

Definition at line 4207 of file clauses.c.

{
    Bitmapset  *notnullattnums = NULL;
 
    Assert(IsA(var, Var));
 
    /* skip upper-level Vars */
    if (var->varlevelsup != 0)
        return false;
 
    /* could the Var be nulled by any outer joins or grouping sets? */
    if (!bms_is_empty(var->varnullingrels))
        return false;
 
    /* system columns cannot be NULL */
    if (var->varattno < 0)
        return true;
 
    /*
     * Check if the Var is defined as NOT NULL.  We retrieve the column NOT
     * NULL constraint information from the corresponding RelOptInfo if it is
     * available; otherwise, we search the hash table for this information.
     */
    if (use_rel_info)
    {
        RelOptInfo *rel = find_base_rel(root, var->varno);
 
        notnullattnums = rel->notnullattnums;
    }
    else
    {
        RangeTblEntry *rte = planner_rt_fetch(var->varno, root);
 
        /*
         * We must skip inheritance parent tables, as some child tables may
         * have a NOT NULL constraint for a column while others may not.  This
         * cannot happen with partitioned tables, though.
         */
        if (rte->inh && rte->relkind != RELKIND_PARTITIONED_TABLE)
            return false;
 
        notnullattnums = find_relation_notnullatts(root, rte->relid);
    }
 
    if (var->varattno > 0 &&
        bms_is_member(var->varattno, notnullattnums))
        return true;
 
    return false;
}

References Assert(), bms_is_empty, bms_is_member(), find_base_rel(), find_relation_notnullatts(), RangeTblEntry::inh, IsA, RelOptInfo::notnullattnums, planner_rt_fetch, root, Var::varattno, Var::varlevelsup, and Var::varno.

Referenced by eval_const_expressions_mutator(), and expr_is_nonnullable().