#include "postgres.h"
#include "access/htup_details.h"
#include "catalog/pg_aggregate.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/nodeFuncs.h"
#include "nodes/supportnodes.h"
#include "optimizer/clauses.h"
#include "optimizer/cost.h"
#include "optimizer/optimizer.h"
#include "optimizer/plancat.h"
#include "optimizer/planmain.h"
#include "parser/analyze.h"
#include "parser/parse_agg.h"
#include "parser/parse_coerce.h"
#include "parser/parse_func.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/lsyscache.h"
#include "utils/memutils.h"
#include "utils/syscache.h"
#include "utils/typcache.h"

Include dependency graph for clauses.c:

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	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 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, HeapTuple func_tuple)

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

static List *	fetch_function_defaults (HeapTuple func_tuple)

static void	recheck_cast_function_args (List *args, Oid result_type, 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)

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_volatile_functions (Node *clause)

static bool	contain_volatile_functions_checker (Oid func_id, void *context)

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 (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)

Node *	estimate_expression_value (PlannerInfo root, Node node)

List *	expand_function_arguments (List *args, 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)

Macro Definition Documentation

◆ CCDN_CASETESTEXPR_OK

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

Definition at line 996 of file clauses.c.

Referenced by contain_context_dependent_node_walker().

◆ ece_all_arguments_const

#define ece_all_arguments_const ( node ) (!expression_tree_walker((Node *) (node), contain_non_const_walker, NULL))

Definition at line 2063 of file clauses.c.

Referenced by eval_const_expressions_mutator().

◆ 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 2067 of file clauses.c.

Referenced by eval_const_expressions_mutator().

◆ ece_generic_processing

#define ece_generic_processing ( node )

Value:

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

(void *) context)

expression_tree_mutator

Node * expression_tree_mutator(Node *node, Node *(*mutator)(), void *context)

Definition: nodeFuncs.c:2565

Node

Definition: nodes.h:527

eval_const_expressions_mutator

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

Definition: clauses.c:2077

Definition at line 2054 of file clauses.c.

Referenced by eval_const_expressions_mutator().

Function Documentation

◆ add_function_defaults()

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

static

Definition at line 3840 of file clauses.c.

References elog, ERROR, fetch_function_defaults(), GETSTRUCT, list_concat_copy(), list_copy_tail(), and list_length().

Referenced by expand_function_arguments().

 {
     Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
     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) - funcform->pronargs;
     if (ndelete < 0)
         elog(ERROR, "not enough default arguments");
     if (ndelete > 0)
         defaults = list_copy_tail(defaults, ndelete);
 
     /* And form the combined argument list, not modifying the input list */
     return list_concat_copy(args, defaults);
 }

◆ CommuteOpExpr()

void CommuteOpExpr ( OpExpr * clause )

Definition at line 1892 of file clauses.c.

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

Referenced by get_switched_clauses().

 {
     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;
 }

◆ contain_agg_clause()

bool contain_agg_clause ( Node * clause )

Definition at line 169 of file clauses.c.

References contain_agg_clause_walker().

Referenced by get_eclass_for_sort_expr(), and subquery_planner().

 {
     return contain_agg_clause_walker(clause, NULL);
 }

◆ contain_agg_clause_walker()

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

static

Definition at line 175 of file clauses.c.

References Assert, expression_tree_walker(), and IsA.

Referenced by contain_agg_clause().

 {
     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);
 }

◆ contain_context_dependent_node()

static bool contain_context_dependent_node ( Node * clause )

static

Definition at line 989 of file clauses.c.

References contain_context_dependent_node_walker().

Referenced by inline_function().

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

◆ contain_context_dependent_node_walker()

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

static

Definition at line 999 of file clauses.c.

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

Referenced by contain_context_dependent_node().

 {
     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,
                                          (void *) 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,
                                   (void *) flags);
 }

◆ contain_exec_param()

bool contain_exec_param	(	Node *	clause,
		List *	param_ids
	)

Definition at line 947 of file clauses.c.

References contain_exec_param_walker().

Referenced by test_opexpr_is_hashable().

 {
     return contain_exec_param_walker(clause, param_ids);
 }

◆ contain_exec_param_walker()

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

static

Definition at line 953 of file clauses.c.

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

Referenced by contain_exec_param().

 {
     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);
 }

◆ contain_leaked_vars()

bool contain_leaked_vars ( Node * clause )

Definition at line 1073 of file clauses.c.

References contain_leaked_vars_walker().

Referenced by make_restrictinfo_internal(), and qual_is_pushdown_safe().

 {
     return contain_leaked_vars_walker(clause, NULL);
 }

◆ contain_leaked_vars_checker()

static bool contain_leaked_vars_checker	(	Oid	func_id,
		void *	context
	)

static

Definition at line 1079 of file clauses.c.

References get_func_leakproof().

Referenced by contain_leaked_vars_walker().

 {
     return !get_func_leakproof(func_id);
 }

◆ contain_leaked_vars_walker()

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

static

Definition at line 1085 of file clauses.c.

References MinMaxExpr::args, check_functions_in_node(), TypeCacheEntry::cmp_proc, contain_leaked_vars_checker(), contain_var_clause(), expression_tree_walker(), forthree, get_func_leakproof(), get_opcode(), RowCompareExpr::largs, lfirst, lfirst_oid, lookup_type_cache(), MinMaxExpr::minmaxtype, nodeTag, OidIsValid, RowCompareExpr::opnos, RowCompareExpr::rargs, T_ArrayCoerceExpr, T_ArrayExpr, T_BooleanTest, T_BoolExpr, T_CaseExpr, T_CaseTestExpr, T_CoerceViaIO, T_CollateExpr, T_Const, T_CurrentOfExpr, T_DistinctExpr, T_FieldSelect, T_FieldStore, T_FuncExpr, T_List, T_MinMaxExpr, T_NamedArgExpr, T_NextValueExpr, T_NullIfExpr, T_NullTest, T_OpExpr, T_Param, T_RelabelType, T_RowCompareExpr, T_RowExpr, T_ScalarArrayOpExpr, T_SQLValueFunction, T_SubscriptingRef, T_Var, and TYPECACHE_CMP_PROC.

Referenced by contain_leaked_vars().

 {
     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_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:
         case T_SubscriptingRef:
 
             /*
              * 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_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);
 }

◆ contain_mutable_functions()

bool contain_mutable_functions ( Node * clause )

Definition at line 357 of file clauses.c.

References contain_mutable_functions_walker().

Referenced by can_minmax_aggs(), check_index_predicates(), CheckMutability(), ComputePartitionAttrs(), cookDefault(), 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().

 {
     return contain_mutable_functions_walker(clause, NULL);
 }

◆ contain_mutable_functions_checker()

static bool contain_mutable_functions_checker	(	Oid	func_id,
		void *	context
	)

static

Definition at line 363 of file clauses.c.

References func_volatile().

Referenced by contain_mutable_functions_walker().

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

◆ contain_mutable_functions_walker()

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

static

Definition at line 369 of file clauses.c.

References check_functions_in_node(), contain_mutable_functions_checker(), expression_tree_walker(), IsA, and query_tree_walker().

Referenced by contain_mutable_functions().

 {
     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, 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);
 }

◆ contain_non_const_walker()

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

static

Definition at line 3297 of file clauses.c.

References expression_tree_walker(), and IsA.

 {
     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;
 }

◆ contain_nonstrict_functions()

bool contain_nonstrict_functions ( Node * clause )

Definition at line 806 of file clauses.c.

References contain_nonstrict_functions_walker().

Referenced by inline_function(), process_equivalence(), and pullup_replace_vars_callback().

 {
     return contain_nonstrict_functions_walker(clause, NULL);
 }

◆ contain_nonstrict_functions_checker()

static bool contain_nonstrict_functions_checker	(	Oid	func_id,
		void *	context
	)

static

Definition at line 812 of file clauses.c.

References func_strict().

Referenced by contain_nonstrict_functions_walker().

 {
     return !func_strict(func_id);
 }

◆ contain_nonstrict_functions_walker()

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

static

Definition at line 818 of file clauses.c.

References AND_EXPR, arg, BoolExpr::boolop, check_functions_in_node(), contain_nonstrict_functions_checker(), expression_tree_walker(), IsA, and OR_EXPR.

Referenced by contain_nonstrict_functions().

 {
     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))
     {
         /*
          * subscripting assignment is nonstrict, but subscripting itself is
          * strict
          */
         if (((SubscriptingRef *) node)->refassgnexpr != NULL)
             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;
 
     /* 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);
 }

◆ contain_subplans()

bool contain_subplans ( Node * clause )

Definition at line 322 of file clauses.c.

References contain_subplans_walker().

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

 {
     return contain_subplans_walker(clause, NULL);
 }

◆ contain_subplans_walker()

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

static

Definition at line 328 of file clauses.c.

References expression_tree_walker(), and IsA.

Referenced by contain_subplans().

 {
     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);
 }

◆ contain_volatile_functions()

bool contain_volatile_functions ( Node * clause )

Definition at line 436 of file clauses.c.

References contain_volatile_functions_walker().

Referenced by AddRelationNewConstraints(), apply_child_basequals(), check_hashjoinable(), check_mergejoinable(), check_output_expressions(), compute_semijoin_info(), convert_ANY_sublink_to_join(), convert_EXISTS_sublink_to_join(), convert_EXISTS_to_ANY(), CopyFrom(), distribute_qual_to_rels(), estimate_num_groups(), ExecInitWindowAgg(), expand_indexqual_rowcompare(), find_compatible_agg(), get_eclass_for_sort_expr(), 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(), IsTidEqualAnyClause(), IsTidEqualClause(), make_sort_input_target(), match_clause_to_ordering_op(), match_clause_to_partition_key(), match_opclause_to_indexcol(), match_rowcompare_to_indexcol(), match_saopclause_to_indexcol(), process_implied_equality(), qual_is_pushdown_safe(), remove_unused_subquery_outputs(), SS_process_ctes(), and subquery_planner().

 {
     return contain_volatile_functions_walker(clause, NULL);
 }

◆ contain_volatile_functions_checker()

static bool contain_volatile_functions_checker	(	Oid	func_id,
		void *	context
	)

static

Definition at line 442 of file clauses.c.

References func_volatile().

Referenced by contain_volatile_functions_walker().

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

◆ contain_volatile_functions_not_nextval()

bool contain_volatile_functions_not_nextval ( Node * clause )

Definition at line 486 of file clauses.c.

References contain_volatile_functions_not_nextval_walker().

Referenced by BeginCopyFrom().

 {
     return contain_volatile_functions_not_nextval_walker(clause, NULL);
 }

◆ contain_volatile_functions_not_nextval_checker()

static bool contain_volatile_functions_not_nextval_checker	(	Oid	func_id,
		void *	context
	)

static

Definition at line 492 of file clauses.c.

References func_volatile().

Referenced by contain_volatile_functions_not_nextval_walker().

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

◆ contain_volatile_functions_not_nextval_walker()

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

static

Definition at line 499 of file clauses.c.

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

Referenced by contain_volatile_functions_not_nextval().

 {
     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);
 }

◆ contain_volatile_functions_walker()

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

static

Definition at line 448 of file clauses.c.

References check_functions_in_node(), contain_volatile_functions_checker(), expression_tree_walker(), IsA, and query_tree_walker().

Referenced by contain_volatile_functions().

 {
     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;
     }
 
     /*
      * 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);
 }

◆ contain_window_function()

bool contain_window_function ( Node * clause )

Definition at line 206 of file clauses.c.

References contain_windowfuncs().

Referenced by get_eclass_for_sort_expr(), and qual_is_pushdown_safe().

 {
     return contain_windowfuncs(clause);
 }

◆ ece_function_is_safe()

static bool ece_function_is_safe	(	Oid	funcid,
		eval_const_expressions_context *	context
	)

static

Definition at line 3313 of file clauses.c.

References eval_const_expressions_context::estimate, and func_volatile().

Referenced by eval_const_expressions_mutator().

 {
     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;
 }

◆ estimate_expression_value()

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

Definition at line 2032 of file clauses.c.

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

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

 {
     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);
 }

◆ eval_const_expressions()

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

Definition at line 1999 of file clauses.c.

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

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

 {
     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);
 }

◆ eval_const_expressions_mutator()

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

static

Definition at line 2077 of file clauses.c.

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, NullTest::argisrow, 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, CaseExpr::casecollid, CaseExpr::casetype, castNode, CoalesceExpr::coalescecollid, CoalesceExpr::coalescetype, COERCE_IMPLICIT_CAST, CoerceViaIO::coerceformat, CoerceToDomain::coercionformat, CollateExpr::collOid, Const::constisnull, Const::consttype, Const::constvalue, contain_mutable_functions(), ConvertRowtypeExpr::convertformat, 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, evaluate_expr(), expand_function_arguments(), CaseWhen::expr, exprCollation(), expression_tree_mutator(), exprType(), exprTypmod(), FieldSelect::fieldnum, FuncExpr::funccollid, FuncExpr::funcformat, FuncExpr::funcid, FuncExpr::funcresulttype, FuncExpr::funcretset, FuncExpr::funcvariadic, get_typlenbyval(), getTypeInputInfo(), getTypeOutputInfo(), HeapTupleIsValid, WindowFunc::inputcollid, FuncExpr::inputcollid, OpExpr::inputcollid, 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(), 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(), makeNode, makeNullConst(), makeVar(), negate_clause(), NIL, nodeTag, NOT_EXPR, NullTest::nulltesttype, ParamListInfoData::numParams, ObjectIdGetDatum, OidIsValid, OpExpr::opcollid, OpExpr::opfuncid, ScalarArrayOpExpr::opfuncid, OpExpr::opno, OpExpr::opresulttype, OpExpr::opretset, OR_EXPR, PARAM_EXTERN, PARAM_FLAG_CONST, Param::paramcollid, ParamListInfoData::paramFetch, Param::paramid, Param::paramkind, ParamListInfoData::params, Param::paramtype, Param::paramtypmod, ParamExternData::pflags, PlaceHolderVar::phexpr, PROCOID, ParamExternData::ptype, record_plan_type_dependency(), RelabelType::relabelformat, ReleaseSysCache(), CaseWhen::result, FieldSelect::resultcollid, RelabelType::resultcollid, CoerceViaIO::resultcollid, CoerceToDomain::resultcollid, FieldSelect::resulttype, RelabelType::resulttype, CoerceViaIO::resulttype, ConvertRowtypeExpr::resulttype, CoerceToDomain::resulttype, FieldSelect::resulttypmod, RelabelType::resulttypmod, CoerceToDomain::resulttypmod, eval_const_expressions_context::root, RowExpr::row_typeid, rowtype_field_matches(), SearchSysCache1(), set_opfuncid(), set_sa_opfuncid(), simplify_and_arguments(), simplify_boolean_equality(), simplify_function(), simplify_or_arguments(), T_AlternativeSubPlan, T_ArrayCoerceExpr, T_ArrayExpr, T_BooleanTest, T_BoolExpr, T_CaseExpr, T_CaseTestExpr, T_CoalesceExpr, T_CoerceToDomain, T_CoerceViaIO, T_CollateExpr, T_ConvertRowtypeExpr, T_DistinctExpr, T_FieldSelect, T_FuncExpr, T_MinMaxExpr, T_NullTest, T_OpExpr, T_Param, T_PlaceHolderVar, T_RelabelType, T_RowExpr, T_ScalarArrayOpExpr, T_SQLValueFunction, T_SubPlan, T_SubscriptingRef, T_WindowFunc, Expr::type, ParamExternData::value, WindowFunc::winagg, WindowFunc::wincollid, WindowFunc::winfnoid, WindowFunc::winref, WindowFunc::winstar, and WindowFunc::wintype.

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

 {
     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;
 
                             get_typlenbyval(param->paramtype,
                                             &typLen, &typByVal);
                             if (prm->isnull || typByVal)
                                 pval = prm->value;
                             else
                                 pval = datumCopy(prm->value, typByVal, typLen);
                             return (Node *) makeConst(param->paramtype,
                                                       param->paramtypmod,
                                                       param->paramcollid,
                                                       (int) typLen,
                                                       pval,
                                                       prm->isnull,
                                                       typByVal);
                         }
                     }
                 }
 
                 /*
                  * 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, 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,
                                             (void *) 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->winref = expr->winref;
                 newexpr->winstar = expr->winstar;
                 newexpr->winagg = expr->winagg;
                 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,
                                                         (void *) 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_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_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 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);
 
                 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))
                         return (Node *) makeVar(((Var *) arg)->varno,
                                                 fselect->fieldnum,
                                                 fselect->resulttype,
                                                 fselect->resulttypmod,
                                                 fselect->resultcollid,
                                                 ((Var *) arg)->varlevelsup);
                 }
                 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);
                 }
 
                 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 SubscriptingRef 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);
 }

◆ evaluate_expr()

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

Definition at line 4469 of file clauses.c.

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().

 {
     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);
 }

◆ 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 3944 of file clauses.c.

References arg, generate_unaccent_rules::args, FuncExpr::args, COERCE_EXPLICIT_CALL, eval_const_expressions_context::estimate, evaluate_expr(), FuncExpr::funccollid, FuncExpr::funcformat, FuncExpr::funcid, FuncExpr::funcresulttype, FuncExpr::funcretset, FuncExpr::funcvariadic, GETSTRUCT, FuncExpr::inputcollid, IsA, lfirst, FuncExpr::location, makeNode, and makeNullConst().

Referenced by simplify_function().

 {
     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, it could get by without an
      * expected tupdesc, but we still have issues: get_expr_result_type()
      * doesn't know how to extract type info from a RECORD constant, and in
      * the case of a NULL function result there doesn't seem to be any clean
      * way to fix that.  In view of the likelihood of there being still other
      * gotchas, 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);
 }

◆ expand_function_arguments()

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

Definition at line 3727 of file clauses.c.

References add_function_defaults(), arg, generate_unaccent_rules::args, GETSTRUCT, IsA, lfirst, list_length(), recheck_cast_function_args(), and reorder_function_arguments().

Referenced by eval_const_expressions_mutator(), exec_stmt_call(), ExecuteCallStmt(), and simplify_function().

 {
     Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
     bool        has_named_args = false;
     ListCell   *lc;
 
     /* 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, func_tuple);
         /* Recheck argument types and add casts if needed */
         recheck_cast_function_args(args, result_type, func_tuple);
     }
     else if (list_length(args) < funcform->pronargs)
     {
         /* No named args, but we seem to be short some defaults */
         args = add_function_defaults(args, func_tuple);
         /* Recheck argument types and add casts if needed */
         recheck_cast_function_args(args, result_type, func_tuple);
     }
 
     return args;
 }

◆ expression_returns_set_rows()

double expression_returns_set_rows	(	PlannerInfo *	root,
		Node *	clause
	)

Definition at line 281 of file clauses.c.

References clamp_row_est(), FuncExpr::funcid, FuncExpr::funcretset, get_function_rows(), IsA, OpExpr::opfuncid, OpExpr::opretset, and set_opfuncid().

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

 {
     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;
 }

◆ fetch_function_defaults()

static List * fetch_function_defaults ( HeapTuple func_tuple )

static

Definition at line 3865 of file clauses.c.

References castNode, elog, ERROR, pfree(), PROCOID, generate_unaccent_rules::str, stringToNode(), SysCacheGetAttr(), and TextDatumGetCString.

Referenced by add_function_defaults(), and reorder_function_arguments().

 {
     List       *defaults;
     Datum       proargdefaults;
     bool        isnull;
     char       *str;
 
     /* The error cases here shouldn't happen, but check anyway */
     proargdefaults = SysCacheGetAttr(PROCOID, func_tuple,
                                      Anum_pg_proc_proargdefaults,
                                      &isnull);
     if (isnull)
         elog(ERROR, "not enough default arguments");
     str = TextDatumGetCString(proargdefaults);
     defaults = castNode(List, stringToNode(str));
     pfree(str);
     return defaults;
 }

◆ find_forced_null_var()

Var* find_forced_null_var ( Node * node )

Definition at line 1724 of file clauses.c.

References NullTest::arg, BooleanTest::arg, NullTest::argisrow, BooleanTest::booltesttype, IS_NULL, IS_UNKNOWN, IsA, NullTest::nulltesttype, and Var::varlevelsup.

Referenced by check_redundant_nullability_qual(), and find_forced_null_vars().

 {
     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;
 }

◆ find_forced_null_vars()

List* find_forced_null_vars ( Node * node )

Definition at line 1665 of file clauses.c.

References AND_EXPR, BoolExpr::args, BoolExpr::boolop, find_forced_null_var(), find_forced_null_vars(), IsA, lfirst, list_concat(), list_make1, and NIL.

Referenced by find_forced_null_vars(), and reduce_outer_joins_pass2().

 {
     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 = list_make1(var);
     }
     /* 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 = list_concat(result,
                                  find_forced_null_vars(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;
 }

◆ find_nonnullable_rels()

Relids find_nonnullable_rels ( Node * clause )

Definition at line 1247 of file clauses.c.

References find_nonnullable_rels_walker().

Referenced by make_outerjoininfo(), and reduce_outer_joins_pass2().

 {
     return find_nonnullable_rels_walker(clause, true);
 }

◆ find_nonnullable_rels_walker()

static Relids find_nonnullable_rels_walker	(	Node *	node,
		bool	top_level
	)

static

Definition at line 1253 of file clauses.c.

References AND_EXPR, RelabelType::arg, CoerceViaIO::arg, ArrayCoerceExpr::arg, ConvertRowtypeExpr::arg, CollateExpr::arg, NullTest::arg, BooleanTest::arg, NullTest::argisrow, 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, func_strict(), FuncExpr::funcid, IS_FALSE, IS_NOT_NULL, IS_NOT_UNKNOWN, is_strict_saop(), IS_TRUE, IsA, lfirst, NOT_EXPR, NullTest::nulltesttype, OpExpr::opfuncid, OR_EXPR, PlaceHolderVar::phexpr, PlaceHolderVar::phlevelsup, PlaceHolderVar::phrels, set_opfuncid(), Var::varlevelsup, and Var::varno.

Referenced by find_nonnullable_rels().

 {
     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, 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;
 }

◆ find_nonnullable_vars()

List* find_nonnullable_vars ( Node * clause )

Definition at line 1472 of file clauses.c.

References find_nonnullable_vars_walker().

Referenced by reduce_outer_joins_pass2().

 {
     return find_nonnullable_vars_walker(clause, true);
 }

◆ find_nonnullable_vars_walker()

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

static

Definition at line 1478 of file clauses.c.

References AND_EXPR, RelabelType::arg, CoerceViaIO::arg, ArrayCoerceExpr::arg, ConvertRowtypeExpr::arg, CollateExpr::arg, NullTest::arg, BooleanTest::arg, NullTest::argisrow, FuncExpr::args, OpExpr::args, ScalarArrayOpExpr::args, BoolExpr::args, BoolExpr::boolop, BooleanTest::booltesttype, elog, ERROR, func_strict(), FuncExpr::funcid, IS_FALSE, IS_NOT_NULL, IS_NOT_UNKNOWN, is_strict_saop(), IS_TRUE, IsA, lfirst, list_concat(), list_intersection(), list_make1, NIL, NOT_EXPR, NullTest::nulltesttype, OpExpr::opfuncid, OR_EXPR, PlaceHolderVar::phexpr, set_opfuncid(), and Var::varlevelsup.

Referenced by find_nonnullable_vars().

 {
     List       *result = NIL;
     ListCell   *l;
 
     if (node == NULL)
         return NIL;
     if (IsA(node, Var))
     {
         Var        *var = (Var *) node;
 
         if (var->varlevelsup == 0)
             result = list_make1(var);
     }
     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 = list_concat(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) */
                 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 = list_intersection(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, PlaceHolderVar))
     {
         PlaceHolderVar *phv = (PlaceHolderVar *) node;
 
         result = find_nonnullable_vars_walker((Node *) phv->phexpr, top_level);
     }
     return result;
 }

◆ find_window_functions()

WindowFuncLists* find_window_functions	(	Node *	clause,
		Index	maxWinRef
	)

Definition at line 219 of file clauses.c.

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

Referenced by grouping_planner().

 {
     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;
 }

◆ find_window_functions_walker()

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

static

Definition at line 231 of file clauses.c.

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

Referenced by find_window_functions().

 {
     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,
                                   (void *) lists);
 }

◆ 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 4071 of file clauses.c.

References ACL_EXECUTE, ACLCHECK_OK, eval_const_expressions_context::active_fns, ALLOCSET_DEFAULT_SIZES, AllocSetContextCreate, arg, ErrorContextCallback::arg, CollateExpr::arg, generate_unaccent_rules::args, FuncExpr::args, ErrorContextCallback::callback, check_sql_fn_retval(), CMD_SELECT, COERCE_EXPLICIT_CALL, CollateExpr::collOid, Query::commandType, contain_context_dependent_node(), contain_mutable_functions(), contain_nonstrict_functions(), contain_subplans(), contain_volatile_functions(), copyObject, cost_qual_eval(), cpu_operator_cost, Query::cteList, CurrentMemoryContext, Query::distinctClause, elog, ERROR, error_context_stack, eval_const_expressions_mutator(), exprCollation(), exprType(), FmgrHookIsNeeded, free_parsestate(), FromExpr::fromlist, FuncExpr::funccollid, FuncExpr::funcformat, FuncExpr::funcid, FuncExpr::funcresulttype, FuncExpr::funcretset, FuncExpr::funcvariadic, get_expr_result_type(), GETSTRUCT, GetUserId(), Query::groupClause, Query::groupingSets, Query::hasAggs, Query::hasSubLinks, Query::hasTargetSRFs, Query::hasWindowFuncs, Query::havingQual, heap_attisnull(), i, FuncExpr::inputcollid, IsA, Query::jointree, lappend_oid(), lfirst, Query::limitCount, Query::limitOffset, linitial, list_delete_last(), list_length(), list_make1, list_member_oid(), FuncExpr::location, CollateExpr::location, make_parsestate(), makeNode, MemoryContextDelete(), MemoryContextSwitchTo(), NameStr, OidIsValid, ParseState::p_sourcetext, palloc0(), QualCost::per_tuple, pg_parse_query(), pg_proc_aclcheck(), prepare_sql_fn_parse_info(), ErrorContextCallback::previous, PROCOID, inline_error_callback_arg::proname, inline_error_callback_arg::prosrc, FromExpr::quals, querytree(), record_plan_function_dependency(), eval_const_expressions_context::root, Query::rtable, Query::setOperations, Query::sortClause, sql_fn_parser_setup(), sql_inline_error_callback(), QualCost::startup, substitute_actual_parameters(), SysCacheGetAttr(), Query::targetList, TextDatumGetCString, transformTopLevelStmt(), and Query::windowClause.

Referenced by simplify_function().

 {
     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 (pg_proc_aclcheck(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);
 
     /* Fetch the function body */
     tmp = SysCacheGetAttr(PROCOID,
                           func_tuple,
                           Anum_pg_proc_prosrc,
                           &isNull);
     if (isNull)
         elog(ERROR, "null prosrc for function %u", funcid);
     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 = (void *) &callback_arg;
     sqlerrcontext.previous = error_context_stack;
     error_context_stack = &sqlerrcontext;
 
     /*
      * Set up to handle parameters while parsing the function body.  We need a
      * dummy FuncExpr node containing the already-simplified arguments to pass
      * to prepare_sql_fn_parse_info.  (In some cases we don't really need
      * that, but for simplicity we always build it.)
      */
     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;
 
     pinfo = prepare_sql_fn_parse_info(func_tuple,
                                       (Node *) fexpr,
                                       input_collid);
 
     /* fexpr also provides a convenient way to resolve a composite result */
     (void) get_expr_result_type((Node *) fexpr,
                                 NULL,
                                 &rettupdesc);
 
     /*
      * 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;
 
     /*
      * 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,
                             false, NULL))
         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;
 }

◆ inline_set_returning_function()

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

Definition at line 4561 of file clauses.c.

References ACL_EXECUTE, ACLCHECK_OK, ALLOCSET_DEFAULT_SIZES, AllocSetContextCreate, ErrorContextCallback::arg, FuncExpr::args, Assert, BuildDescFromLists(), ErrorContextCallback::callback, check_sql_fn_retval(), check_stack_depth(), CMD_SELECT, Query::commandType, contain_subplans(), contain_volatile_functions(), copyObject, CurrentMemoryContext, elog, ERROR, error_context_stack, FmgrHookIsNeeded, RangeTblFunction::funccolcollations, RangeTblFunction::funccolnames, RangeTblFunction::funccoltypes, RangeTblFunction::funccoltypmods, RangeTblFunction::funcexpr, FuncExpr::funcid, RangeTblEntry::funcordinality, FuncExpr::funcretset, RangeTblEntry::functions, get_expr_result_type(), GETSTRUCT, GetUserId(), heap_attisnull(), HeapTupleIsValid, IsA, linitial, linitial_node, list_length(), list_make1, MemoryContextDelete(), MemoryContextSwitchTo(), NameStr, ObjectIdGetDatum, pg_analyze_and_rewrite_params(), pg_parse_query(), pg_proc_aclcheck(), prepare_sql_fn_parse_info(), ErrorContextCallback::previous, PROCOID, inline_error_callback_arg::proname, inline_error_callback_arg::prosrc, querytree(), record_plan_function_dependency(), ReleaseSysCache(), RTE_FUNCTION, RangeTblEntry::rtekind, SearchSysCache1(), sql_fn_parser_setup(), sql_inline_error_callback(), substitute_actual_srf_parameters(), SysCacheGetAttr(), TextDatumGetCString, TYPEFUNC_COMPOSITE, TYPEFUNC_COMPOSITE_DOMAIN, and TYPEFUNC_RECORD.

Referenced by preprocess_function_rtes().

 {
     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 (pg_proc_aclcheck(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 = SysCacheGetAttr(PROCOID,
                           func_tuple,
                           Anum_pg_proc_prosrc,
                           &isNull);
     if (isNull)
         elog(ERROR, "null prosrc for function %u", func_oid);
     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 = (void *) &callback_arg;
     sqlerrcontext.previous = error_context_stack;
     error_context_stack = &sqlerrcontext;
 
     /*
      * 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);
 
     /*
      * Also resolve the actual function result tupdesc, if composite.  If the
      * function is just declared to return RECORD, dig the info out of the AS
      * clause.
      */
     functypclass = get_expr_result_type((Node *) fexpr, NULL, &rettupdesc);
     if (functypclass == TYPEFUNC_RECORD)
         rettupdesc = BuildDescFromLists(rtfunc->funccolnames,
                                         rtfunc->funccoltypes,
                                         rtfunc->funccoltypmods,
                                         rtfunc->funccolcollations);
 
     /*
      * 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_params(linitial(raw_parsetree_list),
                                                    src,
                                                    (ParserSetupHook) sql_fn_parser_setup,
                                                    pinfo, NULL);
     if (list_length(querytree_list) != 1)
         goto fail;
     querytree = linitial(querytree_list);
 
     /*
      * 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,
                              true, NULL) &&
         (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);
 
     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;
 }

Data Structures

Macros

Functions

Macro Definition Documentation

◆ CCDN_CASETESTEXPR_OK

◆ ece_all_arguments_const

◆ ece_evaluate_expr

◆ ece_generic_processing

Function Documentation

◆ add_function_defaults()

◆ CommuteOpExpr()

◆ contain_agg_clause()

◆ contain_agg_clause_walker()

◆ contain_context_dependent_node()

◆ contain_context_dependent_node_walker()

◆ contain_exec_param()

◆ contain_exec_param_walker()

◆ contain_leaked_vars()

◆ contain_leaked_vars_checker()

◆ contain_leaked_vars_walker()

◆ contain_mutable_functions()

◆ contain_mutable_functions_checker()

◆ contain_mutable_functions_walker()

◆ contain_non_const_walker()

◆ contain_nonstrict_functions()

◆ contain_nonstrict_functions_checker()

◆ contain_nonstrict_functions_walker()

◆ contain_subplans()

◆ contain_subplans_walker()

◆ contain_volatile_functions()

◆ contain_volatile_functions_checker()

◆ contain_volatile_functions_not_nextval()

◆ contain_volatile_functions_not_nextval_checker()

◆ contain_volatile_functions_not_nextval_walker()

◆ contain_volatile_functions_walker()

◆ contain_window_function()

◆ ece_function_is_safe()

◆ estimate_expression_value()

◆ eval_const_expressions()

◆ eval_const_expressions_mutator()

◆ evaluate_expr()

◆ evaluate_function()

◆ expand_function_arguments()

◆ expression_returns_set_rows()

◆ fetch_function_defaults()

◆ find_forced_null_var()

◆ find_forced_null_vars()

◆ find_nonnullable_rels()

◆ find_nonnullable_rels_walker()

◆ find_nonnullable_vars()

◆ find_nonnullable_vars_walker()

◆ find_window_functions()

◆ find_window_functions_walker()

◆ inline_function()

◆ inline_set_returning_function()