rewriteManip.c File Reference

#include "postgres.h"
#include "catalog/pg_type.h"
#include "nodes/makefuncs.h"
#include "nodes/nodeFuncs.h"
#include "nodes/pathnodes.h"
#include "nodes/plannodes.h"
#include "parser/parse_coerce.h"
#include "parser/parse_relation.h"
#include "parser/parsetree.h"
#include "rewrite/rewriteManip.h"

Include dependency graph for rewriteManip.c:

Go to the source code of this file.

Data Structures
struct	contain_aggs_of_level_context
struct	locate_agg_of_level_context
struct	locate_windowfunc_context
struct	OffsetVarNodes_context
struct	ChangeVarNodes_context
struct	IncrementVarSublevelsUp_context
struct	rangeTableEntry_used_context
struct	map_variable_attnos_context
struct	ReplaceVarsFromTargetList_context

Functions
static bool	contain_aggs_of_level_walker (Node *node, contain_aggs_of_level_context *context)
static bool	locate_agg_of_level_walker (Node *node, locate_agg_of_level_context *context)
static bool	contain_windowfuncs_walker (Node *node, void *context)
static bool	locate_windowfunc_walker (Node *node, locate_windowfunc_context *context)
static bool	checkExprHasSubLink_walker (Node *node, void *context)
static Relids	offset_relid_set (Relids relids, int offset)
static Relids	adjust_relid_set (Relids relids, int oldrelid, int newrelid)
bool	contain_aggs_of_level (Node *node, int levelsup)
int	locate_agg_of_level (Node *node, int levelsup)
bool	contain_windowfuncs (Node *node)
int	locate_windowfunc (Node *node)
bool	checkExprHasSubLink (Node *node)
static bool	contains_multiexpr_param (Node *node, void *context)
static bool	OffsetVarNodes_walker (Node *node, OffsetVarNodes_context *context)
void	OffsetVarNodes (Node *node, int offset, int sublevels_up)
static bool	ChangeVarNodes_walker (Node *node, ChangeVarNodes_context *context)
void	ChangeVarNodes (Node *node, int rt_index, int new_index, int sublevels_up)
static bool	IncrementVarSublevelsUp_walker (Node *node, IncrementVarSublevelsUp_context *context)
void	IncrementVarSublevelsUp (Node *node, int delta_sublevels_up, int min_sublevels_up)
void	IncrementVarSublevelsUp_rtable (List *rtable, int delta_sublevels_up, int min_sublevels_up)
static bool	rangeTableEntry_used_walker (Node *node, rangeTableEntry_used_context *context)
bool	rangeTableEntry_used (Node *node, int rt_index, int sublevels_up)
Query *	getInsertSelectQuery (Query *parsetree, Query ***subquery_ptr)
void	AddQual (Query *parsetree, Node *qual)
void	AddInvertedQual (Query *parsetree, Node *qual)
Node *	replace_rte_variables (Node *node, int target_varno, int sublevels_up, replace_rte_variables_callback callback, void *callback_arg, bool *outer_hasSubLinks)
Node *	replace_rte_variables_mutator (Node *node, replace_rte_variables_context *context)
static Node *	map_variable_attnos_mutator (Node *node, map_variable_attnos_context *context)
Node *	map_variable_attnos (Node *node, int target_varno, int sublevels_up, const AttrNumber *attno_map, int map_length, Oid to_rowtype, bool *found_whole_row)
static Node *	ReplaceVarsFromTargetList_callback (Var *var, replace_rte_variables_context *context)
Node *	ReplaceVarsFromTargetList (Node *node, int target_varno, int sublevels_up, RangeTblEntry *target_rte, List *targetlist, ReplaceVarsNoMatchOption nomatch_option, int nomatch_varno, bool *outer_hasSubLinks)

Function Documentation

AddInvertedQual()

void AddInvertedQual	(	Query *	parsetree,
		Node *	qual
	)

Definition at line 1044 of file rewriteManip.c.

References AddQual(), BooleanTest::arg, BooleanTest::booltesttype, IS_NOT_TRUE, BooleanTest::location, and makeNode.

Referenced by CopyAndAddInvertedQual().

{
    BooleanTest *invqual;

    if (qual == NULL)
        return;

    /* Need not copy input qual, because AddQual will... */
    invqual = makeNode(BooleanTest);
    invqual->arg = (Expr *) qual;
    invqual->booltesttype = IS_NOT_TRUE;
    invqual->location = -1;

    AddQual(parsetree, (Node *) invqual);
}

AddQual()

void AddQual	(	Query *	parsetree,
		Node *	qual
	)

Definition at line 976 of file rewriteManip.c.

References Assert, checkExprHasSubLink(), CMD_UTILITY, Query::commandType, contain_aggs_of_level(), copyObject, ereport, errcode(), errmsg(), ERROR, Query::hasSubLinks, IsA, Query::jointree, make_and_qual(), FromExpr::quals, Query::setOperations, and Query::utilityStmt.

Referenced by AddInvertedQual(), rewriteRuleAction(), and rewriteTargetView().

{
    Node       *copy;

    if (qual == NULL)
        return;

    if (parsetree->commandType == CMD_UTILITY)
    {
        /*
         * There's noplace to put the qual on a utility statement.
         *
         * If it's a NOTIFY, silently ignore the qual; this means that the
         * NOTIFY will execute, whether or not there are any qualifying rows.
         * While clearly wrong, this is much more useful than refusing to
         * execute the rule at all, and extra NOTIFY events are harmless for
         * typical uses of NOTIFY.
         *
         * If it isn't a NOTIFY, error out, since unconditional execution of
         * other utility stmts is unlikely to be wanted.  (This case is not
         * currently allowed anyway, but keep the test for safety.)
         */
        if (parsetree->utilityStmt && IsA(parsetree->utilityStmt, NotifyStmt))
            return;
        else
            ereport(ERROR,
                    (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                     errmsg("conditional utility statements are not implemented")));
    }

    if (parsetree->setOperations != NULL)
    {
        /*
         * There's noplace to put the qual on a setop statement, either. (This
         * could be fixed, but right now the planner simply ignores any qual
         * condition on a setop query.)
         */
        ereport(ERROR,
                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                 errmsg("conditional UNION/INTERSECT/EXCEPT statements are not implemented")));
    }

    /* INTERSECT wants the original, but we need to copy - Jan */
    copy = copyObject(qual);

    parsetree->jointree->quals = make_and_qual(parsetree->jointree->quals,
                                               copy);

    /*
     * We had better not have stuck an aggregate into the WHERE clause.
     */
    Assert(!contain_aggs_of_level(copy, 0));

    /*
     * Make sure query is marked correctly if added qual has sublinks. Need
     * not search qual when query is already marked.
     */
    if (!parsetree->hasSubLinks)
        parsetree->hasSubLinks = checkExprHasSubLink(copy);
}

adjust_relid_set()

static Relids adjust_relid_set ( Relids  relids, int  oldrelid, int  newrelid  )

static

Definition at line 661 of file rewriteManip.c.

References bms_add_member(), bms_copy(), bms_del_member(), and bms_is_member().

Referenced by ChangeVarNodes_walker().

{
    if (bms_is_member(oldrelid, relids))
    {
        /* Ensure we have a modifiable copy */
        relids = bms_copy(relids);
        /* Remove old, add new */
        relids = bms_del_member(relids, oldrelid);
        relids = bms_add_member(relids, newrelid);
    }
    return relids;
}

ChangeVarNodes()

void ChangeVarNodes	(	Node *	node,
		int	rt_index,
		int	new_index,
		int	sublevels_up
	)

Definition at line 607 of file rewriteManip.c.

References ChangeVarNodes_walker(), OnConflictExpr::exclRelIndex, IsA, lfirst, ChangeVarNodes_context::new_index, Query::onConflict, query_tree_walker(), Query::resultRelation, Query::rowMarks, ChangeVarNodes_context::rt_index, RowMarkClause::rti, and ChangeVarNodes_context::sublevels_up.

Referenced by add_security_quals(), add_with_check_options(), ApplyRetrieveRule(), CopyAndAddInvertedQual(), get_relation_constraints(), get_relation_info(), inheritance_planner(), rewriteRuleAction(), rewriteTargetView(), set_baserel_partition_constraint(), set_baserel_partition_key_exprs(), and TriggerEnabled().

{
    ChangeVarNodes_context context;

    context.rt_index = rt_index;
    context.new_index = new_index;
    context.sublevels_up = sublevels_up;

    /*
     * Must be prepared to start with a Query or a bare expression tree; if
     * it's a Query, go straight to query_tree_walker to make sure that
     * sublevels_up doesn't get incremented prematurely.
     */
    if (node && IsA(node, Query))
    {
        Query      *qry = (Query *) node;

        /*
         * If we are starting at a Query, and sublevels_up is zero, then we
         * must also fix rangetable indexes in the Query itself --- namely
         * resultRelation and rowMarks entries.  sublevels_up cannot be zero
         * when recursing into a subquery, so there's no need to have the same
         * logic inside ChangeVarNodes_walker.
         */
        if (sublevels_up == 0)
        {
            ListCell   *l;

            if (qry->resultRelation == rt_index)
                qry->resultRelation = new_index;

            /* this is unlikely to ever be used, but ... */
            if (qry->onConflict && qry->onConflict->exclRelIndex == rt_index)
                qry->onConflict->exclRelIndex = new_index;

            foreach(l, qry->rowMarks)
            {
                RowMarkClause *rc = (RowMarkClause *) lfirst(l);

                if (rc->rti == rt_index)
                    rc->rti = new_index;
            }
        }
        query_tree_walker(qry, ChangeVarNodes_walker,
                          (void *) &context, 0);
    }
    else
        ChangeVarNodes_walker(node, &context);
}

ChangeVarNodes_walker()

static bool ChangeVarNodes_walker ( Node *  node, ChangeVarNodes_context *  context  )

static

Definition at line 504 of file rewriteManip.c.

References adjust_relid_set(), Assert, AppendRelInfo::child_relid, CurrentOfExpr::cvarno, expression_tree_walker(), IsA, ChangeVarNodes_context::new_index, AppendRelInfo::parent_relid, PlaceHolderVar::phlevelsup, PlaceHolderVar::phrels, PlanRowMark::prti, query_tree_walker(), ChangeVarNodes_context::rt_index, PlanRowMark::rti, RangeTblRef::rtindex, JoinExpr::rtindex, ChangeVarNodes_context::sublevels_up, Var::varlevelsup, Var::varno, and Var::varnoold.

Referenced by ChangeVarNodes().

{
    if (node == NULL)
        return false;
    if (IsA(node, Var))
    {
        Var        *var = (Var *) node;

        if (var->varlevelsup == context->sublevels_up &&
            var->varno == context->rt_index)
        {
            var->varno = context->new_index;
            var->varnoold = context->new_index;
        }
        return false;
    }
    if (IsA(node, CurrentOfExpr))
    {
        CurrentOfExpr *cexpr = (CurrentOfExpr *) node;

        if (context->sublevels_up == 0 &&
            cexpr->cvarno == context->rt_index)
            cexpr->cvarno = context->new_index;
        return false;
    }
    if (IsA(node, RangeTblRef))
    {
        RangeTblRef *rtr = (RangeTblRef *) node;

        if (context->sublevels_up == 0 &&
            rtr->rtindex == context->rt_index)
            rtr->rtindex = context->new_index;
        /* the subquery itself is visited separately */
        return false;
    }
    if (IsA(node, JoinExpr))
    {
        JoinExpr   *j = (JoinExpr *) node;

        if (context->sublevels_up == 0 &&
            j->rtindex == context->rt_index)
            j->rtindex = context->new_index;
        /* fall through to examine children */
    }
    if (IsA(node, PlaceHolderVar))
    {
        PlaceHolderVar *phv = (PlaceHolderVar *) node;

        if (phv->phlevelsup == context->sublevels_up)
        {
            phv->phrels = adjust_relid_set(phv->phrels,
                                           context->rt_index,
                                           context->new_index);
        }
        /* fall through to examine children */
    }
    if (IsA(node, PlanRowMark))
    {
        PlanRowMark *rowmark = (PlanRowMark *) node;

        if (context->sublevels_up == 0)
        {
            if (rowmark->rti == context->rt_index)
                rowmark->rti = context->new_index;
            if (rowmark->prti == context->rt_index)
                rowmark->prti = context->new_index;
        }
        return false;
    }
    if (IsA(node, AppendRelInfo))
    {
        AppendRelInfo *appinfo = (AppendRelInfo *) node;

        if (context->sublevels_up == 0)
        {
            if (appinfo->parent_relid == context->rt_index)
                appinfo->parent_relid = context->new_index;
            if (appinfo->child_relid == context->rt_index)
                appinfo->child_relid = context->new_index;
        }
        /* fall through to examine children */
    }
    /* Shouldn't need to handle other planner auxiliary nodes here */
    Assert(!IsA(node, SpecialJoinInfo));
    Assert(!IsA(node, PlaceHolderInfo));
    Assert(!IsA(node, MinMaxAggInfo));

    if (IsA(node, Query))
    {
        /* Recurse into subselects */
        bool        result;

        context->sublevels_up++;
        result = query_tree_walker((Query *) node, ChangeVarNodes_walker,
                                   (void *) context, 0);
        context->sublevels_up--;
        return result;
    }
    return expression_tree_walker(node, ChangeVarNodes_walker,
                                  (void *) context);
}

checkExprHasSubLink()

bool checkExprHasSubLink

(

Node *

node

)

Definition at line 277 of file rewriteManip.c.

References checkExprHasSubLink_walker(), QTW_IGNORE_RC_SUBQUERIES, and query_or_expression_tree_walker().

Referenced by AddQual(), flatten_join_alias_vars_mutator(), RelationBuildRowSecurity(), replace_rte_variables_mutator(), rewriteRuleAction(), and rewriteTargetView().

{
    /*
     * If a Query is passed, examine it --- but we should not recurse into
     * sub-Queries that are in its rangetable or CTE list.
     */
    return query_or_expression_tree_walker(node,
                                           checkExprHasSubLink_walker,
                                           NULL,
                                           QTW_IGNORE_RC_SUBQUERIES);
}

checkExprHasSubLink_walker()

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

static

Definition at line 290 of file rewriteManip.c.

References expression_tree_walker(), and IsA.

Referenced by checkExprHasSubLink().

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

contain_aggs_of_level()

bool contain_aggs_of_level	(	Node *	node,
		int	levelsup
	)

Definition at line 67 of file rewriteManip.c.

References contain_aggs_of_level_walker(), query_or_expression_tree_walker(), and contain_aggs_of_level_context::sublevels_up.

Referenced by AddQual(), checkTargetlistEntrySQL92(), and convert_EXISTS_to_ANY().

{
    contain_aggs_of_level_context context;

    context.sublevels_up = levelsup;

    /*
     * Must be prepared to start with a Query or a bare expression tree; if
     * it's a Query, we don't want to increment sublevels_up.
     */
    return query_or_expression_tree_walker(node,
                                           contain_aggs_of_level_walker,
                                           (void *) &context,
                                           0);
}

contain_aggs_of_level_walker()

static bool contain_aggs_of_level_walker ( Node *  node, contain_aggs_of_level_context *  context  )

static

Definition at line 84 of file rewriteManip.c.

References expression_tree_walker(), IsA, query_tree_walker(), and contain_aggs_of_level_context::sublevels_up.

Referenced by contain_aggs_of_level().

{
    if (node == NULL)
        return false;
    if (IsA(node, Aggref))
    {
        if (((Aggref *) node)->agglevelsup == context->sublevels_up)
            return true;        /* abort the tree traversal and return true */
        /* else fall through to examine argument */
    }
    if (IsA(node, GroupingFunc))
    {
        if (((GroupingFunc *) node)->agglevelsup == context->sublevels_up)
            return true;
        /* else fall through to examine argument */
    }
    if (IsA(node, Query))
    {
        /* Recurse into subselects */
        bool        result;

        context->sublevels_up++;
        result = query_tree_walker((Query *) node,
                                   contain_aggs_of_level_walker,
                                   (void *) context, 0);
        context->sublevels_up--;
        return result;
    }
    return expression_tree_walker(node, contain_aggs_of_level_walker,
                                  (void *) context);
}

contain_windowfuncs()

bool contain_windowfuncs

(

Node *

node

)

Definition at line 197 of file rewriteManip.c.

References contain_windowfuncs_walker(), and query_or_expression_tree_walker().

Referenced by checkTargetlistEntrySQL92(), contain_window_function(), and transformWindowFuncCall().

{
    /*
     * Must be prepared to start with a Query or a bare expression tree; if
     * it's a Query, we don't want to increment sublevels_up.
     */
    return query_or_expression_tree_walker(node,
                                           contain_windowfuncs_walker,
                                           NULL,
                                           0);
}

contain_windowfuncs_walker()

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

static

Definition at line 210 of file rewriteManip.c.

References expression_tree_walker(), and IsA.

Referenced by contain_windowfuncs().

{
    if (node == NULL)
        return false;
    if (IsA(node, WindowFunc))
        return true;            /* abort the tree traversal and return true */
    /* Mustn't recurse into subselects */
    return expression_tree_walker(node, contain_windowfuncs_walker,
                                  (void *) context);
}

contains_multiexpr_param()

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

static

Definition at line 306 of file rewriteManip.c.

References expression_tree_walker(), IsA, and PARAM_MULTIEXPR.

Referenced by ReplaceVarsFromTargetList_callback().

{
    if (node == NULL)
        return false;
    if (IsA(node, Param))
    {
        if (((Param *) node)->paramkind == PARAM_MULTIEXPR)
            return true;        /* abort the tree traversal and return true */
        return false;
    }
    return expression_tree_walker(node, contains_multiexpr_param, context);
}

getInsertSelectQuery()

Query* getInsertSelectQuery	(	Query *	parsetree,
		Query ***	subquery_ptr
	)

Definition at line 921 of file rewriteManip.c.

References Assert, CMD_INSERT, CMD_SELECT, Query::commandType, elog, ERROR, FromExpr::fromlist, IsA, Query::jointree, linitial, list_length(), PRS2_NEW_VARNO, PRS2_OLD_VARNO, rt_fetch, Query::rtable, RangeTblRef::rtindex, and RangeTblEntry::subquery.

Referenced by DefineQueryRewrite(), InsertRule(), make_ruledef(), rewriteRuleAction(), and transformRuleStmt().

{
    Query      *selectquery;
    RangeTblEntry *selectrte;
    RangeTblRef *rtr;

    if (subquery_ptr)
        *subquery_ptr = NULL;

    if (parsetree == NULL)
        return parsetree;
    if (parsetree->commandType != CMD_INSERT)
        return parsetree;

    /*
     * Currently, this is ONLY applied to rule-action queries, and so we
     * expect to find the OLD and NEW placeholder entries in the given query.
     * If they're not there, it must be an INSERT/SELECT in which they've been
     * pushed down to the SELECT.
     */
    if (list_length(parsetree->rtable) >= 2 &&
        strcmp(rt_fetch(PRS2_OLD_VARNO, parsetree->rtable)->eref->aliasname,
               "old") == 0 &&
        strcmp(rt_fetch(PRS2_NEW_VARNO, parsetree->rtable)->eref->aliasname,
               "new") == 0)
        return parsetree;
    Assert(parsetree->jointree && IsA(parsetree->jointree, FromExpr));
    if (list_length(parsetree->jointree->fromlist) != 1)
        elog(ERROR, "expected to find SELECT subquery");
    rtr = (RangeTblRef *) linitial(parsetree->jointree->fromlist);
    Assert(IsA(rtr, RangeTblRef));
    selectrte = rt_fetch(rtr->rtindex, parsetree->rtable);
    selectquery = selectrte->subquery;
    if (!(selectquery && IsA(selectquery, Query) &&
          selectquery->commandType == CMD_SELECT))
        elog(ERROR, "expected to find SELECT subquery");
    if (list_length(selectquery->rtable) >= 2 &&
        strcmp(rt_fetch(PRS2_OLD_VARNO, selectquery->rtable)->eref->aliasname,
               "old") == 0 &&
        strcmp(rt_fetch(PRS2_NEW_VARNO, selectquery->rtable)->eref->aliasname,
               "new") == 0)
    {
        if (subquery_ptr)
            *subquery_ptr = &(selectrte->subquery);
        return selectquery;
    }
    elog(ERROR, "could not find rule placeholders");
    return NULL;                /* not reached */
}

IncrementVarSublevelsUp()

void IncrementVarSublevelsUp	(	Node *	node,
		int	delta_sublevels_up,
		int	min_sublevels_up
	)

Definition at line 773 of file rewriteManip.c.

References IncrementVarSublevelsUp_context::delta_sublevels_up, IncrementVarSublevelsUp_walker(), IncrementVarSublevelsUp_context::min_sublevels_up, QTW_EXAMINE_RTES_BEFORE, and query_or_expression_tree_walker().

Referenced by assign_param_for_placeholdervar(), build_minmax_path(), convert_EXISTS_sublink_to_join(), convert_EXISTS_to_ANY(), extract_lateral_references(), flatten_join_alias_vars_mutator(), inline_cte_walker(), pull_up_simple_subquery(), pullup_replace_vars_callback(), replace_outer_agg(), replace_outer_grouping(), ReplaceVarsFromTargetList_callback(), and substitute_actual_srf_parameters_mutator().

{
    IncrementVarSublevelsUp_context context;

    context.delta_sublevels_up = delta_sublevels_up;
    context.min_sublevels_up = min_sublevels_up;

    /*
     * Must be prepared to start with a Query or a bare expression tree; if
     * it's a Query, we don't want to increment sublevels_up.
     */
    query_or_expression_tree_walker(node,
                                    IncrementVarSublevelsUp_walker,
                                    (void *) &context,
                                    QTW_EXAMINE_RTES_BEFORE);
}

IncrementVarSublevelsUp_rtable()

void IncrementVarSublevelsUp_rtable	(	List *	rtable,
		int	delta_sublevels_up,
		int	min_sublevels_up
	)

Definition at line 796 of file rewriteManip.c.

References IncrementVarSublevelsUp_context::delta_sublevels_up, IncrementVarSublevelsUp_walker(), IncrementVarSublevelsUp_context::min_sublevels_up, QTW_EXAMINE_RTES_BEFORE, and range_table_walker().

Referenced by pull_up_simple_union_all().

{
    IncrementVarSublevelsUp_context context;

    context.delta_sublevels_up = delta_sublevels_up;
    context.min_sublevels_up = min_sublevels_up;

    range_table_walker(rtable,
                       IncrementVarSublevelsUp_walker,
                       (void *) &context,
                       QTW_EXAMINE_RTES_BEFORE);
}

IncrementVarSublevelsUp_walker()

static bool IncrementVarSublevelsUp_walker ( Node *  node, IncrementVarSublevelsUp_context *  context  )

static

Definition at line 700 of file rewriteManip.c.

References Aggref::agglevelsup, GroupingFunc::agglevelsup, RangeTblEntry::ctelevelsup, IncrementVarSublevelsUp_context::delta_sublevels_up, elog, ERROR, expression_tree_walker(), IsA, IncrementVarSublevelsUp_context::min_sublevels_up, PlaceHolderVar::phlevelsup, QTW_EXAMINE_RTES_BEFORE, query_tree_walker(), RTE_CTE, RangeTblEntry::rtekind, and Var::varlevelsup.

Referenced by IncrementVarSublevelsUp(), and IncrementVarSublevelsUp_rtable().

{
    if (node == NULL)
        return false;
    if (IsA(node, Var))
    {
        Var        *var = (Var *) node;

        if (var->varlevelsup >= context->min_sublevels_up)
            var->varlevelsup += context->delta_sublevels_up;
        return false;           /* done here */
    }
    if (IsA(node, CurrentOfExpr))
    {
        /* this should not happen */
        if (context->min_sublevels_up == 0)
            elog(ERROR, "cannot push down CurrentOfExpr");
        return false;
    }
    if (IsA(node, Aggref))
    {
        Aggref     *agg = (Aggref *) node;

        if (agg->agglevelsup >= context->min_sublevels_up)
            agg->agglevelsup += context->delta_sublevels_up;
        /* fall through to recurse into argument */
    }
    if (IsA(node, GroupingFunc))
    {
        GroupingFunc *grp = (GroupingFunc *) node;

        if (grp->agglevelsup >= context->min_sublevels_up)
            grp->agglevelsup += context->delta_sublevels_up;
        /* fall through to recurse into argument */
    }
    if (IsA(node, PlaceHolderVar))
    {
        PlaceHolderVar *phv = (PlaceHolderVar *) node;

        if (phv->phlevelsup >= context->min_sublevels_up)
            phv->phlevelsup += context->delta_sublevels_up;
        /* fall through to recurse into argument */
    }
    if (IsA(node, RangeTblEntry))
    {
        RangeTblEntry *rte = (RangeTblEntry *) node;

        if (rte->rtekind == RTE_CTE)
        {
            if (rte->ctelevelsup >= context->min_sublevels_up)
                rte->ctelevelsup += context->delta_sublevels_up;
        }
        return false;           /* allow range_table_walker to continue */
    }
    if (IsA(node, Query))
    {
        /* Recurse into subselects */
        bool        result;

        context->min_sublevels_up++;
        result = query_tree_walker((Query *) node,
                                   IncrementVarSublevelsUp_walker,
                                   (void *) context,
                                   QTW_EXAMINE_RTES_BEFORE);
        context->min_sublevels_up--;
        return result;
    }
    return expression_tree_walker(node, IncrementVarSublevelsUp_walker,
                                  (void *) context);
}

locate_agg_of_level()

int locate_agg_of_level	(	Node *	node,
		int	levelsup
	)

Definition at line 131 of file rewriteManip.c.

References locate_agg_of_level_context::agg_location, locate_agg_of_level_walker(), query_or_expression_tree_walker(), and locate_agg_of_level_context::sublevels_up.

Referenced by check_agg_arguments(), checkTargetlistEntrySQL92(), and parseCheckAggregates().

{
    locate_agg_of_level_context context;

    context.agg_location = -1;  /* in case we find nothing */
    context.sublevels_up = levelsup;

    /*
     * Must be prepared to start with a Query or a bare expression tree; if
     * it's a Query, we don't want to increment sublevels_up.
     */
    (void) query_or_expression_tree_walker(node,
                                           locate_agg_of_level_walker,
                                           (void *) &context,
                                           0);

    return context.agg_location;
}

locate_agg_of_level_walker()

static bool locate_agg_of_level_walker ( Node *  node, locate_agg_of_level_context *  context  )

static

Definition at line 151 of file rewriteManip.c.

References locate_agg_of_level_context::agg_location, expression_tree_walker(), IsA, query_tree_walker(), and locate_agg_of_level_context::sublevels_up.

Referenced by locate_agg_of_level().

{
    if (node == NULL)
        return false;
    if (IsA(node, Aggref))
    {
        if (((Aggref *) node)->agglevelsup == context->sublevels_up &&
            ((Aggref *) node)->location >= 0)
        {
            context->agg_location = ((Aggref *) node)->location;
            return true;        /* abort the tree traversal and return true */
        }
        /* else fall through to examine argument */
    }
    if (IsA(node, GroupingFunc))
    {
        if (((GroupingFunc *) node)->agglevelsup == context->sublevels_up &&
            ((GroupingFunc *) node)->location >= 0)
        {
            context->agg_location = ((GroupingFunc *) node)->location;
            return true;        /* abort the tree traversal and return true */
        }
    }
    if (IsA(node, Query))
    {
        /* Recurse into subselects */
        bool        result;

        context->sublevels_up++;
        result = query_tree_walker((Query *) node,
                                   locate_agg_of_level_walker,
                                   (void *) context, 0);
        context->sublevels_up--;
        return result;
    }
    return expression_tree_walker(node, locate_agg_of_level_walker,
                                  (void *) context);
}

locate_windowfunc()

int locate_windowfunc

(

Node *

node

)

Definition at line 235 of file rewriteManip.c.

References locate_windowfunc_walker(), query_or_expression_tree_walker(), and locate_windowfunc_context::win_location.

Referenced by checkTargetlistEntrySQL92(), and transformWindowFuncCall().

{
    locate_windowfunc_context context;

    context.win_location = -1;  /* in case we find nothing */

    /*
     * Must be prepared to start with a Query or a bare expression tree; if
     * it's a Query, we don't want to increment sublevels_up.
     */
    (void) query_or_expression_tree_walker(node,
                                           locate_windowfunc_walker,
                                           (void *) &context,
                                           0);

    return context.win_location;
}

locate_windowfunc_walker()

static bool locate_windowfunc_walker ( Node *  node, locate_windowfunc_context *  context  )

static

Definition at line 254 of file rewriteManip.c.

References expression_tree_walker(), IsA, and locate_windowfunc_context::win_location.

Referenced by locate_windowfunc().

{
    if (node == NULL)
        return false;
    if (IsA(node, WindowFunc))
    {
        if (((WindowFunc *) node)->location >= 0)
        {
            context->win_location = ((WindowFunc *) node)->location;
            return true;        /* abort the tree traversal and return true */
        }
        /* else fall through to examine argument */
    }
    /* Mustn't recurse into subselects */
    return expression_tree_walker(node, locate_windowfunc_walker,
                                  (void *) context);
}

map_variable_attnos()

Node* map_variable_attnos	(	Node *	node,
		int	target_varno,
		int	sublevels_up,
		const AttrNumber *	attno_map,
		int	map_length,
		Oid	to_rowtype,
		bool *	found_whole_row
	)

Definition at line 1351 of file rewriteManip.c.

References map_variable_attnos_context::attno_map, map_variable_attnos_context::found_whole_row, map_variable_attnos_context::map_length, map_variable_attnos_mutator(), query_or_expression_tree_mutator(), map_variable_attnos_context::sublevels_up, map_variable_attnos_context::target_varno, and map_variable_attnos_context::to_rowtype.

Referenced by ATPrepAlterColumnType(), CompareIndexInfo(), DefineIndex(), ExecInitPartitionInfo(), generateClonedIndexStmt(), map_partition_varattnos(), MergeAttributes(), and transformTableLikeClause().

{
    map_variable_attnos_context context;

    context.target_varno = target_varno;
    context.sublevels_up = sublevels_up;
    context.attno_map = attno_map;
    context.map_length = map_length;
    context.to_rowtype = to_rowtype;
    context.found_whole_row = found_whole_row;

    *found_whole_row = false;

    /*
     * Must be prepared to start with a Query or a bare expression tree; if
     * it's a Query, we don't want to increment sublevels_up.
     */
    return query_or_expression_tree_mutator(node,
                                            map_variable_attnos_mutator,
                                            (void *) &context,
                                            0);
}

map_variable_attnos_mutator()

static Node* map_variable_attnos_mutator ( Node *  node, map_variable_attnos_context *  context  )

static

Definition at line 1231 of file rewriteManip.c.

References ConvertRowtypeExpr::arg, Assert, map_variable_attnos_context::attno_map, COERCE_IMPLICIT_CAST, ConvertRowtypeExpr::convertformat, elog, ERROR, expression_tree_mutator(), map_variable_attnos_context::found_whole_row, IsA, ConvertRowtypeExpr::location, makeNode, map_variable_attnos_context::map_length, OidIsValid, palloc(), query_tree_mutator(), ConvertRowtypeExpr::resulttype, map_variable_attnos_context::sublevels_up, map_variable_attnos_context::target_varno, map_variable_attnos_context::to_rowtype, Var::varattno, Var::varlevelsup, Var::varno, Var::varoattno, and Var::vartype.

Referenced by map_variable_attnos().

{
    if (node == NULL)
        return NULL;
    if (IsA(node, Var))
    {
        Var        *var = (Var *) node;

        if (var->varno == context->target_varno &&
            var->varlevelsup == context->sublevels_up)
        {
            /* Found a matching variable, make the substitution */
            Var        *newvar = (Var *) palloc(sizeof(Var));
            int         attno = var->varattno;

            *newvar = *var;     /* initially copy all fields of the Var */

            if (attno > 0)
            {
                /* user-defined column, replace attno */
                if (attno > context->map_length ||
                    context->attno_map[attno - 1] == 0)
                    elog(ERROR, "unexpected varattno %d in expression to be mapped",
                         attno);
                newvar->varattno = newvar->varoattno = context->attno_map[attno - 1];
            }
            else if (attno == 0)
            {
                /* whole-row variable, warn caller */
                *(context->found_whole_row) = true;

                /* If the caller expects us to convert the Var, do so. */
                if (OidIsValid(context->to_rowtype) &&
                    context->to_rowtype != var->vartype)
                {
                    ConvertRowtypeExpr *r;

                    /* This certainly won't work for a RECORD variable. */
                    Assert(var->vartype != RECORDOID);

                    /* Var itself is changed to the requested type. */
                    newvar->vartype = context->to_rowtype;

                    /*
                     * Add a conversion node on top to convert back to the
                     * original type expected by the expression.
                     */
                    r = makeNode(ConvertRowtypeExpr);
                    r->arg = (Expr *) newvar;
                    r->resulttype = var->vartype;
                    r->convertformat = COERCE_IMPLICIT_CAST;
                    r->location = -1;

                    return (Node *) r;
                }
            }
            return (Node *) newvar;
        }
        /* otherwise fall through to copy the var normally */
    }
    else if (IsA(node, ConvertRowtypeExpr))
    {
        ConvertRowtypeExpr *r = (ConvertRowtypeExpr *) node;
        Var        *var = (Var *) r->arg;

        /*
         * If this is coercing a whole-row Var that we need to convert, then
         * just convert the Var without adding an extra ConvertRowtypeExpr.
         * Effectively we're simplifying var::parenttype::grandparenttype into
         * just var::grandparenttype.  This avoids building stacks of CREs if
         * this function is applied repeatedly.
         */
        if (IsA(var, Var) &&
            var->varno == context->target_varno &&
            var->varlevelsup == context->sublevels_up &&
            var->varattno == 0 &&
            OidIsValid(context->to_rowtype) &&
            context->to_rowtype != var->vartype)
        {
            ConvertRowtypeExpr *newnode;
            Var        *newvar = (Var *) palloc(sizeof(Var));

            /* whole-row variable, warn caller */
            *(context->found_whole_row) = true;

            *newvar = *var;     /* initially copy all fields of the Var */

            /* This certainly won't work for a RECORD variable. */
            Assert(var->vartype != RECORDOID);

            /* Var itself is changed to the requested type. */
            newvar->vartype = context->to_rowtype;

            newnode = (ConvertRowtypeExpr *) palloc(sizeof(ConvertRowtypeExpr));
            *newnode = *r;      /* initially copy all fields of the CRE */
            newnode->arg = (Expr *) newvar;

            return (Node *) newnode;
        }
        /* otherwise fall through to process the expression normally */
    }
    else if (IsA(node, Query))
    {
        /* Recurse into RTE subquery or not-yet-planned sublink subquery */
        Query      *newnode;

        context->sublevels_up++;
        newnode = query_tree_mutator((Query *) node,
                                     map_variable_attnos_mutator,
                                     (void *) context,
                                     0);
        context->sublevels_up--;
        return (Node *) newnode;
    }
    return expression_tree_mutator(node, map_variable_attnos_mutator,
                                   (void *) context);
}

offset_relid_set()

static Relids offset_relid_set ( Relids  relids, int  offset  )

static

Definition at line 472 of file rewriteManip.c.

References bms_add_member(), and bms_next_member().

Referenced by OffsetVarNodes_walker().

{
    Relids      result = NULL;
    int         rtindex;

    rtindex = -1;
    while ((rtindex = bms_next_member(relids, rtindex)) >= 0)
        result = bms_add_member(result, rtindex + offset);
    return result;
}

OffsetVarNodes()

void OffsetVarNodes	(	Node *	node,
		int	offset,
		int	sublevels_up
	)

Definition at line 424 of file rewriteManip.c.

References OnConflictExpr::exclRelIndex, IsA, lfirst, OffsetVarNodes_context::offset, OffsetVarNodes_walker(), Query::onConflict, query_tree_walker(), Query::resultRelation, Query::rowMarks, RowMarkClause::rti, and OffsetVarNodes_context::sublevels_up.

Referenced by convert_EXISTS_sublink_to_join(), pull_up_simple_subquery(), rewriteRuleAction(), and UpdateRangeTableOfViewParse().

{
    OffsetVarNodes_context context;

    context.offset = offset;
    context.sublevels_up = sublevels_up;

    /*
     * Must be prepared to start with a Query or a bare expression tree; if
     * it's a Query, go straight to query_tree_walker to make sure that
     * sublevels_up doesn't get incremented prematurely.
     */
    if (node && IsA(node, Query))
    {
        Query      *qry = (Query *) node;

        /*
         * If we are starting at a Query, and sublevels_up is zero, then we
         * must also fix rangetable indexes in the Query itself --- namely
         * resultRelation, exclRelIndex and rowMarks entries.  sublevels_up
         * cannot be zero when recursing into a subquery, so there's no need
         * to have the same logic inside OffsetVarNodes_walker.
         */
        if (sublevels_up == 0)
        {
            ListCell   *l;

            if (qry->resultRelation)
                qry->resultRelation += offset;

            if (qry->onConflict && qry->onConflict->exclRelIndex)
                qry->onConflict->exclRelIndex += offset;

            foreach(l, qry->rowMarks)
            {
                RowMarkClause *rc = (RowMarkClause *) lfirst(l);

                rc->rti += offset;
            }
        }
        query_tree_walker(qry, OffsetVarNodes_walker,
                          (void *) &context, 0);
    }
    else
        OffsetVarNodes_walker(node, &context);
}

OffsetVarNodes_walker()

static bool OffsetVarNodes_walker ( Node *  node, OffsetVarNodes_context *  context  )

static

Definition at line 340 of file rewriteManip.c.

References Assert, AppendRelInfo::child_relid, CurrentOfExpr::cvarno, expression_tree_walker(), IsA, OffsetVarNodes_context::offset, offset_relid_set(), AppendRelInfo::parent_relid, PlaceHolderVar::phlevelsup, PlaceHolderVar::phrels, query_tree_walker(), RangeTblRef::rtindex, JoinExpr::rtindex, OffsetVarNodes_context::sublevels_up, Var::varlevelsup, Var::varno, and Var::varnoold.

Referenced by OffsetVarNodes().

{
    if (node == NULL)
        return false;
    if (IsA(node, Var))
    {
        Var        *var = (Var *) node;

        if (var->varlevelsup == context->sublevels_up)
        {
            var->varno += context->offset;
            var->varnoold += context->offset;
        }
        return false;
    }
    if (IsA(node, CurrentOfExpr))
    {
        CurrentOfExpr *cexpr = (CurrentOfExpr *) node;

        if (context->sublevels_up == 0)
            cexpr->cvarno += context->offset;
        return false;
    }
    if (IsA(node, RangeTblRef))
    {
        RangeTblRef *rtr = (RangeTblRef *) node;

        if (context->sublevels_up == 0)
            rtr->rtindex += context->offset;
        /* the subquery itself is visited separately */
        return false;
    }
    if (IsA(node, JoinExpr))
    {
        JoinExpr   *j = (JoinExpr *) node;

        if (j->rtindex && context->sublevels_up == 0)
            j->rtindex += context->offset;
        /* fall through to examine children */
    }
    if (IsA(node, PlaceHolderVar))
    {
        PlaceHolderVar *phv = (PlaceHolderVar *) node;

        if (phv->phlevelsup == context->sublevels_up)
        {
            phv->phrels = offset_relid_set(phv->phrels,
                                           context->offset);
        }
        /* fall through to examine children */
    }
    if (IsA(node, AppendRelInfo))
    {
        AppendRelInfo *appinfo = (AppendRelInfo *) node;

        if (context->sublevels_up == 0)
        {
            appinfo->parent_relid += context->offset;
            appinfo->child_relid += context->offset;
        }
        /* fall through to examine children */
    }
    /* Shouldn't need to handle other planner auxiliary nodes here */
    Assert(!IsA(node, PlanRowMark));
    Assert(!IsA(node, SpecialJoinInfo));
    Assert(!IsA(node, PlaceHolderInfo));
    Assert(!IsA(node, MinMaxAggInfo));

    if (IsA(node, Query))
    {
        /* Recurse into subselects */
        bool        result;

        context->sublevels_up++;
        result = query_tree_walker((Query *) node, OffsetVarNodes_walker,
                                   (void *) context, 0);
        context->sublevels_up--;
        return result;
    }
    return expression_tree_walker(node, OffsetVarNodes_walker,
                                  (void *) context);
}

rangeTableEntry_used()

bool rangeTableEntry_used	(	Node *	node,
		int	rt_index,
		int	sublevels_up
	)

Definition at line 889 of file rewriteManip.c.

References query_or_expression_tree_walker(), rangeTableEntry_used_walker(), rangeTableEntry_used_context::rt_index, and rangeTableEntry_used_context::sublevels_up.

Referenced by fireRIRrules(), matchLocks(), rewriteRuleAction(), and transformRuleStmt().

{
    rangeTableEntry_used_context context;

    context.rt_index = rt_index;
    context.sublevels_up = sublevels_up;

    /*
     * Must be prepared to start with a Query or a bare expression tree; if
     * it's a Query, we don't want to increment sublevels_up.
     */
    return query_or_expression_tree_walker(node,
                                           rangeTableEntry_used_walker,
                                           (void *) &context,
                                           0);
}

rangeTableEntry_used_walker()

static bool rangeTableEntry_used_walker ( Node *  node, rangeTableEntry_used_context *  context  )

static

Definition at line 823 of file rewriteManip.c.

References Assert, CurrentOfExpr::cvarno, expression_tree_walker(), IsA, query_tree_walker(), rangeTableEntry_used_context::rt_index, RangeTblRef::rtindex, JoinExpr::rtindex, rangeTableEntry_used_context::sublevels_up, Var::varlevelsup, and Var::varno.

Referenced by rangeTableEntry_used().

{
    if (node == NULL)
        return false;
    if (IsA(node, Var))
    {
        Var        *var = (Var *) node;

        if (var->varlevelsup == context->sublevels_up &&
            var->varno == context->rt_index)
            return true;
        return false;
    }
    if (IsA(node, CurrentOfExpr))
    {
        CurrentOfExpr *cexpr = (CurrentOfExpr *) node;

        if (context->sublevels_up == 0 &&
            cexpr->cvarno == context->rt_index)
            return true;
        return false;
    }
    if (IsA(node, RangeTblRef))
    {
        RangeTblRef *rtr = (RangeTblRef *) node;

        if (rtr->rtindex == context->rt_index &&
            context->sublevels_up == 0)
            return true;
        /* the subquery itself is visited separately */
        return false;
    }
    if (IsA(node, JoinExpr))
    {
        JoinExpr   *j = (JoinExpr *) node;

        if (j->rtindex == context->rt_index &&
            context->sublevels_up == 0)
            return true;
        /* fall through to examine children */
    }
    /* Shouldn't need to handle planner auxiliary nodes here */
    Assert(!IsA(node, PlaceHolderVar));
    Assert(!IsA(node, PlanRowMark));
    Assert(!IsA(node, SpecialJoinInfo));
    Assert(!IsA(node, AppendRelInfo));
    Assert(!IsA(node, PlaceHolderInfo));
    Assert(!IsA(node, MinMaxAggInfo));

    if (IsA(node, Query))
    {
        /* Recurse into subselects */
        bool        result;

        context->sublevels_up++;
        result = query_tree_walker((Query *) node, rangeTableEntry_used_walker,
                                   (void *) context, 0);
        context->sublevels_up--;
        return result;
    }
    return expression_tree_walker(node, rangeTableEntry_used_walker,
                                  (void *) context);
}

replace_rte_variables()

Node* replace_rte_variables	(	Node *	node,
		int	target_varno,
		int	sublevels_up,
		replace_rte_variables_callback	callback,
		void *	callback_arg,
		bool *	outer_hasSubLinks
	)

Definition at line 1084 of file rewriteManip.c.

References replace_rte_variables_context::callback, callback(), replace_rte_variables_context::callback_arg, elog, ERROR, replace_rte_variables_context::inserted_sublink, IsA, query_or_expression_tree_mutator(), replace_rte_variables_mutator(), replace_rte_variables_context::sublevels_up, and replace_rte_variables_context::target_varno.

Referenced by pullup_replace_vars(), pullup_replace_vars_subquery(), and ReplaceVarsFromTargetList().

{
    Node       *result;
    replace_rte_variables_context context;

    context.callback = callback;
    context.callback_arg = callback_arg;
    context.target_varno = target_varno;
    context.sublevels_up = sublevels_up;

    /*
     * We try to initialize inserted_sublink to true if there is no need to
     * detect new sublinks because the query already has some.
     */
    if (node && IsA(node, Query))
        context.inserted_sublink = ((Query *) node)->hasSubLinks;
    else if (outer_hasSubLinks)
        context.inserted_sublink = *outer_hasSubLinks;
    else
        context.inserted_sublink = false;

    /*
     * Must be prepared to start with a Query or a bare expression tree; if
     * it's a Query, we don't want to increment sublevels_up.
     */
    result = query_or_expression_tree_mutator(node,
                                              replace_rte_variables_mutator,
                                              (void *) &context,
                                              0);

    if (context.inserted_sublink)
    {
        if (result && IsA(result, Query))
            ((Query *) result)->hasSubLinks = true;
        else if (outer_hasSubLinks)
            *outer_hasSubLinks = true;
        else
            elog(ERROR, "replace_rte_variables inserted a SubLink, but has noplace to record it");
    }

    return result;
}

replace_rte_variables_mutator()

Node* replace_rte_variables_mutator	(	Node *	node,
		replace_rte_variables_context *	context
	)

Definition at line 1131 of file rewriteManip.c.

References replace_rte_variables_context::callback, checkExprHasSubLink(), CurrentOfExpr::cvarno, ereport, errcode(), errmsg(), ERROR, expression_tree_mutator(), Query::hasSubLinks, replace_rte_variables_context::inserted_sublink, IsA, query_tree_mutator(), replace_rte_variables_mutator(), replace_rte_variables_context::sublevels_up, replace_rte_variables_context::target_varno, Var::varlevelsup, and Var::varno.

Referenced by pullup_replace_vars_callback(), replace_rte_variables(), replace_rte_variables_mutator(), and ReplaceVarsFromTargetList_callback().

{
    if (node == NULL)
        return NULL;
    if (IsA(node, Var))
    {
        Var        *var = (Var *) node;

        if (var->varno == context->target_varno &&
            var->varlevelsup == context->sublevels_up)
        {
            /* Found a matching variable, make the substitution */
            Node       *newnode;

            newnode = context->callback(var, context);
            /* Detect if we are adding a sublink to query */
            if (!context->inserted_sublink)
                context->inserted_sublink = checkExprHasSubLink(newnode);
            return newnode;
        }
        /* otherwise fall through to copy the var normally */
    }
    else if (IsA(node, CurrentOfExpr))
    {
        CurrentOfExpr *cexpr = (CurrentOfExpr *) node;

        if (cexpr->cvarno == context->target_varno &&
            context->sublevels_up == 0)
        {
            /*
             * We get here if a WHERE CURRENT OF expression turns out to apply
             * to a view.  Someday we might be able to translate the
             * expression to apply to an underlying table of the view, but
             * right now it's not implemented.
             */
            ereport(ERROR,
                    (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                     errmsg("WHERE CURRENT OF on a view is not implemented")));
        }
        /* otherwise fall through to copy the expr normally */
    }
    else if (IsA(node, Query))
    {
        /* Recurse into RTE subquery or not-yet-planned sublink subquery */
        Query      *newnode;
        bool        save_inserted_sublink;

        context->sublevels_up++;
        save_inserted_sublink = context->inserted_sublink;
        context->inserted_sublink = ((Query *) node)->hasSubLinks;
        newnode = query_tree_mutator((Query *) node,
                                     replace_rte_variables_mutator,
                                     (void *) context,
                                     0);
        newnode->hasSubLinks |= context->inserted_sublink;
        context->inserted_sublink = save_inserted_sublink;
        context->sublevels_up--;
        return (Node *) newnode;
    }
    return expression_tree_mutator(node, replace_rte_variables_mutator,
                                   (void *) context);
}

ReplaceVarsFromTargetList()

Node* ReplaceVarsFromTargetList	(	Node *	node,
		int	target_varno,
		int	sublevels_up,
		RangeTblEntry *	target_rte,
		List *	targetlist,
		ReplaceVarsNoMatchOption	nomatch_option,
		int	nomatch_varno,
		bool *	outer_hasSubLinks
	)

Definition at line 1510 of file rewriteManip.c.

References ReplaceVarsFromTargetList_context::nomatch_option, ReplaceVarsFromTargetList_context::nomatch_varno, replace_rte_variables(), ReplaceVarsFromTargetList_callback(), ReplaceVarsFromTargetList_context::target_rte, and ReplaceVarsFromTargetList_context::targetlist.

Referenced by CopyAndAddInvertedQual(), rewriteRuleAction(), rewriteTargetView(), and subquery_push_qual().

{
    ReplaceVarsFromTargetList_context context;

    context.target_rte = target_rte;
    context.targetlist = targetlist;
    context.nomatch_option = nomatch_option;
    context.nomatch_varno = nomatch_varno;

    return replace_rte_variables(node, target_varno, sublevels_up,
                                 ReplaceVarsFromTargetList_callback,
                                 (void *) &context,
                                 outer_hasSubLinks);
}

ReplaceVarsFromTargetList_callback()

static Node* ReplaceVarsFromTargetList_callback ( Var *  var, replace_rte_variables_context *  context  )

static

Definition at line 1406 of file rewriteManip.c.

References RowExpr::args, replace_rte_variables_context::callback_arg, COERCE_IMPLICIT_CAST, coerce_to_domain(), COERCION_IMPLICIT, RowExpr::colnames, contains_multiexpr_param(), copyObject, elog, ereport, errcode(), errmsg(), ERROR, expandRTE(), get_tle_by_resno(), IncrementVarSublevelsUp(), InvalidAttrNumber, InvalidOid, Var::location, RowExpr::location, makeNode, makeNullConst(), ReplaceVarsFromTargetList_context::nomatch_option, ReplaceVarsFromTargetList_context::nomatch_varno, replace_rte_variables_mutator(), REPLACEVARS_CHANGE_VARNO, REPLACEVARS_REPORT_ERROR, REPLACEVARS_SUBSTITUTE_NULL, RowExpr::row_format, RowExpr::row_typeid, ReplaceVarsFromTargetList_context::target_rte, ReplaceVarsFromTargetList_context::targetlist, Var::varattno, Var::varcollid, Var::varlevelsup, Var::varno, Var::varnoold, Var::vartype, and Var::vartypmod.

Referenced by ReplaceVarsFromTargetList().

{
    ReplaceVarsFromTargetList_context *rcon = (ReplaceVarsFromTargetList_context *) context->callback_arg;
    TargetEntry *tle;

    if (var->varattno == InvalidAttrNumber)
    {
        /* Must expand whole-tuple reference into RowExpr */
        RowExpr    *rowexpr;
        List       *colnames;
        List       *fields;

        /*
         * If generating an expansion for a var of a named rowtype (ie, this
         * is a plain relation RTE), then we must include dummy items for
         * dropped columns.  If the var is RECORD (ie, this is a JOIN), then
         * omit dropped columns.  Either way, attach column names to the
         * RowExpr for use of ruleutils.c.
         */
        expandRTE(rcon->target_rte,
                  var->varno, var->varlevelsup, var->location,
                  (var->vartype != RECORDOID),
                  &colnames, &fields);
        /* Adjust the generated per-field Vars... */
        fields = (List *) replace_rte_variables_mutator((Node *) fields,
                                                        context);
        rowexpr = makeNode(RowExpr);
        rowexpr->args = fields;
        rowexpr->row_typeid = var->vartype;
        rowexpr->row_format = COERCE_IMPLICIT_CAST;
        rowexpr->colnames = colnames;
        rowexpr->location = var->location;

        return (Node *) rowexpr;
    }

    /* Normal case referencing one targetlist element */
    tle = get_tle_by_resno(rcon->targetlist, var->varattno);

    if (tle == NULL || tle->resjunk)
    {
        /* Failed to find column in targetlist */
        switch (rcon->nomatch_option)
        {
            case REPLACEVARS_REPORT_ERROR:
                /* fall through, throw error below */
                break;

            case REPLACEVARS_CHANGE_VARNO:
                var = (Var *) copyObject(var);
                var->varno = rcon->nomatch_varno;
                var->varnoold = rcon->nomatch_varno;
                return (Node *) var;

            case REPLACEVARS_SUBSTITUTE_NULL:

                /*
                 * If Var is of domain type, we should add a CoerceToDomain
                 * node, in case there is a NOT NULL domain constraint.
                 */
                return coerce_to_domain((Node *) makeNullConst(var->vartype,
                                                               var->vartypmod,
                                                               var->varcollid),
                                        InvalidOid, -1,
                                        var->vartype,
                                        COERCION_IMPLICIT,
                                        COERCE_IMPLICIT_CAST,
                                        -1,
                                        false);
        }
        elog(ERROR, "could not find replacement targetlist entry for attno %d",
             var->varattno);
        return NULL;            /* keep compiler quiet */
    }
    else
    {
        /* Make a copy of the tlist item to return */
        Expr       *newnode = copyObject(tle->expr);

        /* Must adjust varlevelsup if tlist item is from higher query */
        if (var->varlevelsup > 0)
            IncrementVarSublevelsUp((Node *) newnode, var->varlevelsup, 0);

        /*
         * Check to see if the tlist item contains a PARAM_MULTIEXPR Param,
         * and throw error if so.  This case could only happen when expanding
         * an ON UPDATE rule's NEW variable and the referenced tlist item in
         * the original UPDATE command is part of a multiple assignment. There
         * seems no practical way to handle such cases without multiple
         * evaluation of the multiple assignment's sub-select, which would
         * create semantic oddities that users of rules would probably prefer
         * not to cope with.  So treat it as an unimplemented feature.
         */
        if (contains_multiexpr_param((Node *) newnode, NULL))
            ereport(ERROR,
                    (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                     errmsg("NEW variables in ON UPDATE rules cannot reference columns that are part of a multiple assignment in the subject UPDATE command")));

        return (Node *) newnode;
    }
}