rewriteManip.h File Reference

#include "nodes/parsenodes.h"

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Data Structures
struct	replace_rte_variables_context

Typedefs
typedef struct replace_rte_variables_context	replace_rte_variables_context
typedef Node *(*	replace_rte_variables_callback) (Var *var, replace_rte_variables_context *context)
typedef enum ReplaceVarsNoMatchOption	ReplaceVarsNoMatchOption

Enumerations
enum	ReplaceVarsNoMatchOption { REPLACEVARS_REPORT_ERROR , REPLACEVARS_CHANGE_VARNO , REPLACEVARS_SUBSTITUTE_NULL }

Functions
void	CombineRangeTables (List **dst_rtable, List **dst_perminfos, List *src_rtable, List *src_perminfos)
void	OffsetVarNodes (Node *node, int offset, int sublevels_up)
void	ChangeVarNodes (Node *node, int rt_index, int new_index, int sublevels_up)
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)
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)
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)
Node *	add_nulling_relids (Node *node, const Bitmapset *target_relids, const Bitmapset *added_relids)
Node *	remove_nulling_relids (Node *node, const Bitmapset *removable_relids, const Bitmapset *except_relids)
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)
Node *	map_variable_attnos (Node *node, int target_varno, int sublevels_up, const struct AttrMap *attno_map, Oid to_rowtype, bool *found_whole_row)
Node *	ReplaceVarsFromTargetList (Node *node, int target_varno, int sublevels_up, RangeTblEntry *target_rte, List *targetlist, ReplaceVarsNoMatchOption nomatch_option, int nomatch_varno, bool *outer_hasSubLinks)

Typedef Documentation

replace_rte_variables_callback

typedef Node*(* replace_rte_variables_callback) (Var *var, replace_rte_variables_context *context)

Definition at line 24 of file rewriteManip.h.

replace_rte_variables_context

typedef struct replace_rte_variables_context replace_rte_variables_context

Definition at line 1 of file rewriteManip.h.

ReplaceVarsNoMatchOption

typedef enum ReplaceVarsNoMatchOption ReplaceVarsNoMatchOption

Enumeration Type Documentation

ReplaceVarsNoMatchOption

enum ReplaceVarsNoMatchOption

Enumerator
REPLACEVARS_REPORT_ERROR
REPLACEVARS_CHANGE_VARNO
REPLACEVARS_SUBSTITUTE_NULL

Definition at line 36 of file rewriteManip.h.

{
    REPLACEVARS_REPORT_ERROR,   /* throw error if no match */
    REPLACEVARS_CHANGE_VARNO,   /* change the Var's varno, nothing else */
    REPLACEVARS_SUBSTITUTE_NULL,    /* replace with a NULL Const */
} ReplaceVarsNoMatchOption;

Function Documentation

add_nulling_relids()

Node* add_nulling_relids	(	Node *	node,
		const Bitmapset *	target_relids,
		const Bitmapset *	added_relids
	)

Definition at line 1139 of file rewriteManip.c.

{
    add_nulling_relids_context context;
 
    context.target_relids = target_relids;
    context.added_relids = added_relids;
    context.sublevels_up = 0;
    return query_or_expression_tree_mutator(node,
                                            add_nulling_relids_mutator,
                                            &context,
                                            0);
}

References add_nulling_relids_mutator(), context, and query_or_expression_tree_mutator.

Referenced by deconstruct_distribute_oj_quals(), mark_nullable_by_grouping(), pullup_replace_vars_callback(), and transform_MERGE_to_join().

AddInvertedQual()

void AddInvertedQual	(	Query *	parsetree,
		Node *	qual
	)

Definition at line 1115 of file rewriteManip.c.

{
    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);
}

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

Referenced by CopyAndAddInvertedQual().

AddQual()

void AddQual	(	Query *	parsetree,
		Node *	qual
	)

Definition at line 1047 of file rewriteManip.c.

{
    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);
}

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

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

ChangeVarNodes()

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

Definition at line 668 of file rewriteManip.c.

{
    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, mergeTargetRelation, 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
         * ChangeVarNodes_walker.
         */
        if (sublevels_up == 0)
        {
            ListCell   *l;
 
            if (qry->resultRelation == rt_index)
                qry->resultRelation = new_index;
 
            if (qry->mergeTargetRelation == rt_index)
                qry->mergeTargetRelation = 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, &context, 0);
    }
    else
        ChangeVarNodes_walker(node, &context);
}

References ChangeVarNodes_walker(), context, OnConflictExpr::exclRelIndex, IsA, lfirst, Query::onConflict, query_tree_walker, Query::rowMarks, and RowMarkClause::rti.

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

checkExprHasSubLink()

bool checkExprHasSubLink

(

Node *

node

)

Definition at line 292 of file rewriteManip.c.

{
    /*
     * 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);
}

References checkExprHasSubLink_walker(), QTW_IGNORE_RC_SUBQUERIES, and query_or_expression_tree_walker.

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

CombineRangeTables()

void CombineRangeTables	(	List **	dst_rtable,
		List **	dst_perminfos,
		List *	src_rtable,
		List *	src_perminfos
	)

Definition at line 347 of file rewriteManip.c.

{
    ListCell   *l;
    int         offset = list_length(*dst_perminfos);
 
    if (offset > 0)
    {
        foreach(l, src_rtable)
        {
            RangeTblEntry *rte = lfirst_node(RangeTblEntry, l);
 
            if (rte->perminfoindex > 0)
                rte->perminfoindex += offset;
        }
    }
 
    *dst_perminfos = list_concat(*dst_perminfos, src_perminfos);
    *dst_rtable = list_concat(*dst_rtable, src_rtable);
}

References lfirst_node, list_concat(), and list_length().

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

contain_aggs_of_level()

bool contain_aggs_of_level	(	Node *	node,
		int	levelsup
	)

Definition at line 85 of file rewriteManip.c.

{
    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,
                                           &context,
                                           0);
}

References contain_aggs_of_level_walker(), context, and query_or_expression_tree_walker.

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

contain_windowfuncs()

bool contain_windowfuncs

(

Node *

node

)

Definition at line 214 of file rewriteManip.c.

{
    /*
     * 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);
}

References contain_windowfuncs_walker(), and query_or_expression_tree_walker.

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

getInsertSelectQuery()

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

Definition at line 989 of file rewriteManip.c.

{
    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);
    if (!IsA(rtr, RangeTblRef))
        elog(ERROR, "expected to find SELECT subquery");
    selectrte = rt_fetch(rtr->rtindex, parsetree->rtable);
    if (!(selectrte->rtekind == RTE_SUBQUERY &&
          selectrte->subquery &&
          IsA(selectrte->subquery, Query) &&
          selectrte->subquery->commandType == CMD_SELECT))
        elog(ERROR, "expected to find SELECT subquery");
    selectquery = selectrte->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 */
}

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, RTE_SUBQUERY, RangeTblEntry::rtekind, RangeTblRef::rtindex, and RangeTblEntry::subquery.

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

IncrementVarSublevelsUp()

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

Definition at line 841 of file rewriteManip.c.

{
    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,
                                    &context,
                                    QTW_EXAMINE_RTES_BEFORE);
}

References context, IncrementVarSublevelsUp_walker(), 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_group_exprs_mutator(), flatten_join_alias_vars_mutator(), inline_cte_walker(), pull_up_simple_subquery(), pullup_replace_vars_callback(), replace_outer_agg(), replace_outer_grouping(), ReplaceVarsFromTargetList_callback(), rewriteSearchAndCycle(), and substitute_actual_srf_parameters_mutator().

IncrementVarSublevelsUp_rtable()

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

Definition at line 864 of file rewriteManip.c.

{
    IncrementVarSublevelsUp_context context;
 
    context.delta_sublevels_up = delta_sublevels_up;
    context.min_sublevels_up = min_sublevels_up;
 
    range_table_walker(rtable,
                       IncrementVarSublevelsUp_walker,
                       &context,
                       QTW_EXAMINE_RTES_BEFORE);
}

References context, IncrementVarSublevelsUp_walker(), QTW_EXAMINE_RTES_BEFORE, and range_table_walker.

Referenced by pull_up_simple_union_all().

locate_agg_of_level()

int locate_agg_of_level	(	Node *	node,
		int	levelsup
	)

Definition at line 149 of file rewriteManip.c.

{
    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,
                                           &context,
                                           0);
 
    return context.agg_location;
}

References context, locate_agg_of_level_walker(), and query_or_expression_tree_walker.

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

locate_windowfunc()

int locate_windowfunc

(

Node *

node

)

Definition at line 251 of file rewriteManip.c.

{
    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,
                                           &context,
                                           0);
 
    return context.win_location;
}

References context, locate_windowfunc_walker(), and query_or_expression_tree_walker.

Referenced by checkTargetlistEntrySQL92(), and transformWindowFuncCall().

map_variable_attnos()

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

OffsetVarNodes()

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

Definition at line 476 of file rewriteManip.c.

{
    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, mergeTargetRelation, 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->mergeTargetRelation)
                qry->mergeTargetRelation += 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, &context, 0);
    }
    else
        OffsetVarNodes_walker(node, &context);
}

References context, OnConflictExpr::exclRelIndex, IsA, lfirst, OffsetVarNodes_walker(), Query::onConflict, query_tree_walker, Query::rowMarks, and RowMarkClause::rti.

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

rangeTableEntry_used()

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

Definition at line 957 of file rewriteManip.c.

{
    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,
                                           &context,
                                           0);
}

References context, query_or_expression_tree_walker, and rangeTableEntry_used_walker().

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

remove_nulling_relids()

Node* remove_nulling_relids	(	Node *	node,
		const Bitmapset *	removable_relids,
		const Bitmapset *	except_relids
	)

Definition at line 1227 of file rewriteManip.c.

{
    remove_nulling_relids_context context;
 
    context.removable_relids = removable_relids;
    context.except_relids = except_relids;
    context.sublevels_up = 0;
    return query_or_expression_tree_mutator(node,
                                            remove_nulling_relids_mutator,
                                            &context,
                                            0);
}

References context, query_or_expression_tree_mutator, and remove_nulling_relids_mutator().

Referenced by deconstruct_distribute_oj_quals(), have_partkey_equi_join(), make_group_input_target(), make_pathkeys_for_sortclauses_extended(), reconsider_full_join_clause(), reduce_outer_joins(), remove_useless_result_rtes(), and set_upper_references().

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 1334 of file rewriteManip.c.

{
    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,
                                              &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;
}

References callback(), context, elog, ERROR, IsA, query_or_expression_tree_mutator, and replace_rte_variables_mutator().

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

replace_rte_variables_mutator()

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

Definition at line 1381 of file rewriteManip.c.

{
    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,
                                     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, context);
}

References checkExprHasSubLink(), context, CurrentOfExpr::cvarno, ereport, errcode(), errmsg(), ERROR, expression_tree_mutator, IsA, query_tree_mutator, Var::varlevelsup, and Var::varno.

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

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 1759 of file rewriteManip.c.

{
    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,
                                 &context,
                                 outer_hasSubLinks);
}

References context, replace_rte_variables(), and ReplaceVarsFromTargetList_callback().

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