parse_relation.c File Reference

#include "postgres.h"
#include <ctype.h>
#include "access/htup_details.h"
#include "access/relation.h"
#include "access/sysattr.h"
#include "access/table.h"
#include "catalog/heap.h"
#include "catalog/namespace.h"
#include "catalog/pg_type.h"
#include "funcapi.h"
#include "nodes/makefuncs.h"
#include "nodes/nodeFuncs.h"
#include "parser/parse_enr.h"
#include "parser/parse_relation.h"
#include "parser/parse_type.h"
#include "parser/parsetree.h"
#include "storage/lmgr.h"
#include "utils/builtins.h"
#include "utils/lsyscache.h"
#include "utils/rel.h"
#include "utils/syscache.h"
#include "utils/varlena.h"

Include dependency graph for parse_relation.c:

Go to the source code of this file.

Data Structures
struct	FuzzyAttrMatchState

Macros
#define	MAX_FUZZY_DISTANCE   3

Functions
static ParseNamespaceItem *	scanNameSpaceForRefname (ParseState *pstate, const char *refname, int location)
static ParseNamespaceItem *	scanNameSpaceForRelid (ParseState *pstate, Oid relid, int location)
static void	check_lateral_ref_ok (ParseState *pstate, ParseNamespaceItem *nsitem, int location)
static int	scanRTEForColumn (ParseState *pstate, RangeTblEntry *rte, Alias *eref, const char *colname, int location, int fuzzy_rte_penalty, FuzzyAttrMatchState *fuzzystate)
static void	markRTEForSelectPriv (ParseState *pstate, int rtindex, AttrNumber col)
static void	expandRelation (Oid relid, Alias *eref, int rtindex, int sublevels_up, int location, bool include_dropped, List **colnames, List **colvars)
static void	expandTupleDesc (TupleDesc tupdesc, Alias *eref, int count, int offset, int rtindex, int sublevels_up, int location, bool include_dropped, List **colnames, List **colvars)
static int	specialAttNum (const char *attname)
static bool	rte_visible_if_lateral (ParseState *pstate, RangeTblEntry *rte)
static bool	rte_visible_if_qualified (ParseState *pstate, RangeTblEntry *rte)
static bool	isQueryUsingTempRelation_walker (Node *node, void *context)
ParseNamespaceItem *	refnameNamespaceItem (ParseState *pstate, const char *schemaname, const char *refname, int location, int *sublevels_up)
CommonTableExpr *	scanNameSpaceForCTE (ParseState *pstate, const char *refname, Index *ctelevelsup)
static bool	isFutureCTE (ParseState *pstate, const char *refname)
bool	scanNameSpaceForENR (ParseState *pstate, const char *refname)
static RangeTblEntry *	searchRangeTableForRel (ParseState *pstate, RangeVar *relation)
void	checkNameSpaceConflicts (ParseState *pstate, List *namespace1, List *namespace2)
ParseNamespaceItem *	GetNSItemByRangeTablePosn (ParseState *pstate, int varno, int sublevels_up)
RangeTblEntry *	GetRTEByRangeTablePosn (ParseState *pstate, int varno, int sublevels_up)
CommonTableExpr *	GetCTEForRTE (ParseState *pstate, RangeTblEntry *rte, int rtelevelsup)
static void	updateFuzzyAttrMatchState (int fuzzy_rte_penalty, FuzzyAttrMatchState *fuzzystate, RangeTblEntry *rte, const char *actual, const char *match, int attnum)
Node *	scanNSItemForColumn (ParseState *pstate, ParseNamespaceItem *nsitem, int sublevels_up, const char *colname, int location)
Node *	colNameToVar (ParseState *pstate, const char *colname, bool localonly, int location)
static FuzzyAttrMatchState *	searchRangeTableForCol (ParseState *pstate, const char *alias, const char *colname, int location)
void	markNullableIfNeeded (ParseState *pstate, Var *var)
void	markVarForSelectPriv (ParseState *pstate, Var *var)
static void	buildRelationAliases (TupleDesc tupdesc, Alias *alias, Alias *eref)
static char *	chooseScalarFunctionAlias (Node *funcexpr, char *funcname, Alias *alias, int nfuncs)
static ParseNamespaceItem *	buildNSItemFromTupleDesc (RangeTblEntry *rte, Index rtindex, RTEPermissionInfo *perminfo, TupleDesc tupdesc)
static ParseNamespaceItem *	buildNSItemFromLists (RangeTblEntry *rte, Index rtindex, List *coltypes, List *coltypmods, List *colcollations)
Relation	parserOpenTable (ParseState *pstate, const RangeVar *relation, int lockmode)
ParseNamespaceItem *	addRangeTableEntry (ParseState *pstate, RangeVar *relation, Alias *alias, bool inh, bool inFromCl)
ParseNamespaceItem *	addRangeTableEntryForRelation (ParseState *pstate, Relation rel, int lockmode, Alias *alias, bool inh, bool inFromCl)
ParseNamespaceItem *	addRangeTableEntryForSubquery (ParseState *pstate, Query *subquery, Alias *alias, bool lateral, bool inFromCl)
ParseNamespaceItem *	addRangeTableEntryForFunction (ParseState *pstate, List *funcnames, List *funcexprs, List *coldeflists, RangeFunction *rangefunc, bool lateral, bool inFromCl)
ParseNamespaceItem *	addRangeTableEntryForTableFunc (ParseState *pstate, TableFunc *tf, Alias *alias, bool lateral, bool inFromCl)
ParseNamespaceItem *	addRangeTableEntryForValues (ParseState *pstate, List *exprs, List *coltypes, List *coltypmods, List *colcollations, Alias *alias, bool lateral, bool inFromCl)
ParseNamespaceItem *	addRangeTableEntryForJoin (ParseState *pstate, List *colnames, ParseNamespaceColumn *nscolumns, JoinType jointype, int nummergedcols, List *aliasvars, List *leftcols, List *rightcols, Alias *join_using_alias, Alias *alias, bool inFromCl)
ParseNamespaceItem *	addRangeTableEntryForCTE (ParseState *pstate, CommonTableExpr *cte, Index levelsup, RangeVar *rv, bool inFromCl)
ParseNamespaceItem *	addRangeTableEntryForENR (ParseState *pstate, RangeVar *rv, bool inFromCl)
bool	isLockedRefname (ParseState *pstate, const char *refname)
void	addNSItemToQuery (ParseState *pstate, ParseNamespaceItem *nsitem, bool addToJoinList, bool addToRelNameSpace, bool addToVarNameSpace)
void	expandRTE (RangeTblEntry *rte, int rtindex, int sublevels_up, int location, bool include_dropped, List **colnames, List **colvars)
List *	expandNSItemVars (ParseState *pstate, ParseNamespaceItem *nsitem, int sublevels_up, int location, List **colnames)
List *	expandNSItemAttrs (ParseState *pstate, ParseNamespaceItem *nsitem, int sublevels_up, bool require_col_privs, int location)
char *	get_rte_attribute_name (RangeTblEntry *rte, AttrNumber attnum)
bool	get_rte_attribute_is_dropped (RangeTblEntry *rte, AttrNumber attnum)
TargetEntry *	get_tle_by_resno (List *tlist, AttrNumber resno)
RowMarkClause *	get_parse_rowmark (Query *qry, Index rtindex)
int	attnameAttNum (Relation rd, const char *attname, bool sysColOK)
const NameData *	attnumAttName (Relation rd, int attid)
Oid	attnumTypeId (Relation rd, int attid)
Oid	attnumCollationId (Relation rd, int attid)
void	errorMissingRTE (ParseState *pstate, RangeVar *relation)
void	errorMissingColumn (ParseState *pstate, const char *relname, const char *colname, int location)
static ParseNamespaceItem *	findNSItemForRTE (ParseState *pstate, RangeTblEntry *rte)
bool	isQueryUsingTempRelation (Query *query)
RTEPermissionInfo *	addRTEPermissionInfo (List **rteperminfos, RangeTblEntry *rte)
RTEPermissionInfo *	getRTEPermissionInfo (List *rteperminfos, RangeTblEntry *rte)

Macro Definition Documentation

MAX_FUZZY_DISTANCE

#define MAX_FUZZY_DISTANCE   3

Definition at line 75 of file parse_relation.c.

Function Documentation

addNSItemToQuery()

void addNSItemToQuery	(	ParseState *	pstate,
		ParseNamespaceItem *	nsitem,
		bool	addToJoinList,
		bool	addToRelNameSpace,
		bool	addToVarNameSpace
	)

Definition at line 2625 of file parse_relation.c.

{
    if (addToJoinList)
    {
        RangeTblRef *rtr = makeNode(RangeTblRef);
 
        rtr->rtindex = nsitem->p_rtindex;
        pstate->p_joinlist = lappend(pstate->p_joinlist, rtr);
    }
    if (addToRelNameSpace || addToVarNameSpace)
    {
        /* Set the new nsitem's visibility flags correctly */
        nsitem->p_rel_visible = addToRelNameSpace;
        nsitem->p_cols_visible = addToVarNameSpace;
        nsitem->p_lateral_only = false;
        nsitem->p_lateral_ok = true;
        pstate->p_namespace = lappend(pstate->p_namespace, nsitem);
    }
}

References lappend(), makeNode, ParseNamespaceItem::p_cols_visible, ParseState::p_joinlist, ParseNamespaceItem::p_lateral_ok, ParseNamespaceItem::p_lateral_only, ParseState::p_namespace, ParseNamespaceItem::p_rel_visible, ParseNamespaceItem::p_rtindex, and RangeTblRef::rtindex.

Referenced by AddRelationNewConstraints(), AlterPolicy(), CreatePolicy(), CreateTriggerFiringOn(), DefineRelation(), DoCopy(), setTargetTable(), test_rls_hooks_permissive(), test_rls_hooks_restrictive(), transformAlterTableStmt(), transformIndexStmt(), transformInsertStmt(), transformMergeStmt(), transformOnConflictClause(), transformPartitionSpec(), TransformPubWhereClauses(), transformRuleStmt(), transformSetOperationStmt(), transformStatsStmt(), and transformValuesClause().

addRangeTableEntry()

ParseNamespaceItem* addRangeTableEntry	(	ParseState *	pstate,
		RangeVar *	relation,
		Alias *	alias,
		bool	inh,
		bool	inFromCl
	)

Definition at line 1470 of file parse_relation.c.

{
    RangeTblEntry *rte = makeNode(RangeTblEntry);
    RTEPermissionInfo *perminfo;
    char       *refname = alias ? alias->aliasname : relation->relname;
    LOCKMODE    lockmode;
    Relation    rel;
    ParseNamespaceItem *nsitem;
 
    Assert(pstate != NULL);
 
    rte->rtekind = RTE_RELATION;
    rte->alias = alias;
 
    /*
     * Identify the type of lock we'll need on this relation.  It's not the
     * query's target table (that case is handled elsewhere), so we need
     * either RowShareLock if it's locked by FOR UPDATE/SHARE, or plain
     * AccessShareLock otherwise.
     */
    lockmode = isLockedRefname(pstate, refname) ? RowShareLock : AccessShareLock;
 
    /*
     * Get the rel's OID.  This access also ensures that we have an up-to-date
     * relcache entry for the rel.  Since this is typically the first access
     * to a rel in a statement, we must open the rel with the proper lockmode.
     */
    rel = parserOpenTable(pstate, relation, lockmode);
    rte->relid = RelationGetRelid(rel);
    rte->relkind = rel->rd_rel->relkind;
    rte->rellockmode = lockmode;
 
    /*
     * Build the list of effective column names using user-supplied aliases
     * and/or actual column names.
     */
    rte->eref = makeAlias(refname, NIL);
    buildRelationAliases(rel->rd_att, alias, rte->eref);
 
    /*
     * Set flags and initialize access permissions.
     *
     * The initial default on access checks is always check-for-READ-access,
     * which is the right thing for all except target tables.
     */
    rte->lateral = false;
    rte->inh = inh;
    rte->inFromCl = inFromCl;
 
    perminfo = addRTEPermissionInfo(&pstate->p_rteperminfos, rte);
    perminfo->requiredPerms = ACL_SELECT;
 
    /*
     * Add completed RTE to pstate's range table list, so that we know its
     * index.  But we don't add it to the join list --- caller must do that if
     * appropriate.
     */
    pstate->p_rtable = lappend(pstate->p_rtable, rte);
 
    /*
     * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
     * list --- caller must do that if appropriate.
     */
    nsitem = buildNSItemFromTupleDesc(rte, list_length(pstate->p_rtable),
                                      perminfo, rel->rd_att);
 
    /*
     * Drop the rel refcount, but keep the access lock till end of transaction
     * so that the table can't be deleted or have its schema modified
     * underneath us.
     */
    table_close(rel, NoLock);
 
    return nsitem;
}

References AccessShareLock, ACL_SELECT, addRTEPermissionInfo(), RangeTblEntry::alias, Alias::aliasname, Assert(), buildNSItemFromTupleDesc(), buildRelationAliases(), RangeTblEntry::eref, RangeTblEntry::inFromCl, RangeTblEntry::inh, isLockedRefname(), lappend(), RangeTblEntry::lateral, list_length(), makeAlias(), makeNode, NIL, NoLock, ParseState::p_rtable, ParseState::p_rteperminfos, parserOpenTable(), RelationData::rd_att, RelationData::rd_rel, RelationGetRelid, RangeTblEntry::relid, RangeTblEntry::relkind, RangeTblEntry::rellockmode, RangeVar::relname, RTEPermissionInfo::requiredPerms, RowShareLock, RTE_RELATION, RangeTblEntry::rtekind, and table_close().

Referenced by transformTableEntry().

addRangeTableEntryForCTE()

ParseNamespaceItem* addRangeTableEntryForCTE	(	ParseState *	pstate,
		CommonTableExpr *	cte,
		Index	levelsup,
		RangeVar *	rv,
		bool	inFromCl
	)

Definition at line 2319 of file parse_relation.c.

{
    RangeTblEntry *rte = makeNode(RangeTblEntry);
    Alias      *alias = rv->alias;
    char       *refname = alias ? alias->aliasname : cte->ctename;
    Alias      *eref;
    int         numaliases;
    int         varattno;
    ListCell   *lc;
    int         n_dontexpand_columns = 0;
    ParseNamespaceItem *psi;
 
    Assert(pstate != NULL);
 
    rte->rtekind = RTE_CTE;
    rte->ctename = cte->ctename;
    rte->ctelevelsup = levelsup;
 
    /* Self-reference if and only if CTE's parse analysis isn't completed */
    rte->self_reference = !IsA(cte->ctequery, Query);
    Assert(cte->cterecursive || !rte->self_reference);
    /* Bump the CTE's refcount if this isn't a self-reference */
    if (!rte->self_reference)
        cte->cterefcount++;
 
    /*
     * We throw error if the CTE is INSERT/UPDATE/DELETE without RETURNING.
     * This won't get checked in case of a self-reference, but that's OK
     * because data-modifying CTEs aren't allowed to be recursive anyhow.
     */
    if (IsA(cte->ctequery, Query))
    {
        Query      *ctequery = (Query *) cte->ctequery;
 
        if (ctequery->commandType != CMD_SELECT &&
            ctequery->returningList == NIL)
            ereport(ERROR,
                    (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                     errmsg("WITH query \"%s\" does not have a RETURNING clause",
                            cte->ctename),
                     parser_errposition(pstate, rv->location)));
    }
 
    rte->coltypes = list_copy(cte->ctecoltypes);
    rte->coltypmods = list_copy(cte->ctecoltypmods);
    rte->colcollations = list_copy(cte->ctecolcollations);
 
    rte->alias = alias;
    if (alias)
        eref = copyObject(alias);
    else
        eref = makeAlias(refname, NIL);
    numaliases = list_length(eref->colnames);
 
    /* fill in any unspecified alias columns */
    varattno = 0;
    foreach(lc, cte->ctecolnames)
    {
        varattno++;
        if (varattno > numaliases)
            eref->colnames = lappend(eref->colnames, lfirst(lc));
    }
    if (varattno < numaliases)
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
                 errmsg("table \"%s\" has %d columns available but %d columns specified",
                        refname, varattno, numaliases)));
 
    rte->eref = eref;
 
    if (cte->search_clause)
    {
        rte->eref->colnames = lappend(rte->eref->colnames, makeString(cte->search_clause->search_seq_column));
        if (cte->search_clause->search_breadth_first)
            rte->coltypes = lappend_oid(rte->coltypes, RECORDOID);
        else
            rte->coltypes = lappend_oid(rte->coltypes, RECORDARRAYOID);
        rte->coltypmods = lappend_int(rte->coltypmods, -1);
        rte->colcollations = lappend_oid(rte->colcollations, InvalidOid);
 
        n_dontexpand_columns += 1;
    }
 
    if (cte->cycle_clause)
    {
        rte->eref->colnames = lappend(rte->eref->colnames, makeString(cte->cycle_clause->cycle_mark_column));
        rte->coltypes = lappend_oid(rte->coltypes, cte->cycle_clause->cycle_mark_type);
        rte->coltypmods = lappend_int(rte->coltypmods, cte->cycle_clause->cycle_mark_typmod);
        rte->colcollations = lappend_oid(rte->colcollations, cte->cycle_clause->cycle_mark_collation);
 
        rte->eref->colnames = lappend(rte->eref->colnames, makeString(cte->cycle_clause->cycle_path_column));
        rte->coltypes = lappend_oid(rte->coltypes, RECORDARRAYOID);
        rte->coltypmods = lappend_int(rte->coltypmods, -1);
        rte->colcollations = lappend_oid(rte->colcollations, InvalidOid);
 
        n_dontexpand_columns += 2;
    }
 
    /*
     * Set flags and access permissions.
     *
     * Subqueries are never checked for access rights, so no need to perform
     * addRTEPermissionInfo().
     */
    rte->lateral = false;
    rte->inh = false;           /* never true for subqueries */
    rte->inFromCl = inFromCl;
 
    /*
     * Add completed RTE to pstate's range table list, so that we know its
     * index.  But we don't add it to the join list --- caller must do that if
     * appropriate.
     */
    pstate->p_rtable = lappend(pstate->p_rtable, rte);
 
    /*
     * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
     * list --- caller must do that if appropriate.
     */
    psi = buildNSItemFromLists(rte, list_length(pstate->p_rtable),
                               rte->coltypes, rte->coltypmods,
                               rte->colcollations);
 
    /*
     * The columns added by search and cycle clauses are not included in star
     * expansion in queries contained in the CTE.
     */
    if (rte->ctelevelsup > 0)
        for (int i = 0; i < n_dontexpand_columns; i++)
            psi->p_nscolumns[list_length(psi->p_names->colnames) - 1 - i].p_dontexpand = true;
 
    return psi;
}

References RangeTblEntry::alias, RangeVar::alias, Alias::aliasname, Assert(), buildNSItemFromLists(), CMD_SELECT, RangeTblEntry::colcollations, Alias::colnames, RangeTblEntry::coltypes, RangeTblEntry::coltypmods, Query::commandType, copyObject, RangeTblEntry::ctelevelsup, RangeTblEntry::ctename, CommonTableExpr::ctename, CommonTableExpr::ctequery, RangeTblEntry::eref, ereport, errcode(), errmsg(), ERROR, i, if(), RangeTblEntry::inFromCl, RangeTblEntry::inh, InvalidOid, IsA, lappend(), lappend_int(), lappend_oid(), RangeTblEntry::lateral, lfirst, list_copy(), list_length(), RangeVar::location, makeAlias(), makeNode, makeString(), NIL, ParseNamespaceColumn::p_dontexpand, ParseNamespaceItem::p_names, ParseNamespaceItem::p_nscolumns, ParseState::p_rtable, parser_errposition(), Query::returningList, RTE_CTE, RangeTblEntry::rtekind, and RangeTblEntry::self_reference.

Referenced by getNSItemForSpecialRelationTypes().

addRangeTableEntryForENR()

ParseNamespaceItem* addRangeTableEntryForENR	(	ParseState *	pstate,
		RangeVar *	rv,
		bool	inFromCl
	)

Definition at line 2471 of file parse_relation.c.

{
    RangeTblEntry *rte = makeNode(RangeTblEntry);
    Alias      *alias = rv->alias;
    char       *refname = alias ? alias->aliasname : rv->relname;
    EphemeralNamedRelationMetadata enrmd;
    TupleDesc   tupdesc;
    int         attno;
 
    Assert(pstate != NULL);
    enrmd = get_visible_ENR(pstate, rv->relname);
    Assert(enrmd != NULL);
 
    switch (enrmd->enrtype)
    {
        case ENR_NAMED_TUPLESTORE:
            rte->rtekind = RTE_NAMEDTUPLESTORE;
            break;
 
        default:
            elog(ERROR, "unexpected enrtype: %d", enrmd->enrtype);
            return NULL;        /* for fussy compilers */
    }
 
    /*
     * Record dependency on a relation.  This allows plans to be invalidated
     * if they access transition tables linked to a table that is altered.
     */
    rte->relid = enrmd->reliddesc;
 
    /*
     * Build the list of effective column names using user-supplied aliases
     * and/or actual column names.
     */
    tupdesc = ENRMetadataGetTupDesc(enrmd);
    rte->eref = makeAlias(refname, NIL);
    buildRelationAliases(tupdesc, alias, rte->eref);
 
    /* Record additional data for ENR, including column type info */
    rte->enrname = enrmd->name;
    rte->enrtuples = enrmd->enrtuples;
    rte->coltypes = NIL;
    rte->coltypmods = NIL;
    rte->colcollations = NIL;
    for (attno = 1; attno <= tupdesc->natts; ++attno)
    {
        Form_pg_attribute att = TupleDescAttr(tupdesc, attno - 1);
 
        if (att->attisdropped)
        {
            /* Record zeroes for a dropped column */
            rte->coltypes = lappend_oid(rte->coltypes, InvalidOid);
            rte->coltypmods = lappend_int(rte->coltypmods, 0);
            rte->colcollations = lappend_oid(rte->colcollations, InvalidOid);
        }
        else
        {
            /* Let's just make sure we can tell this isn't dropped */
            if (att->atttypid == InvalidOid)
                elog(ERROR, "atttypid is invalid for non-dropped column in \"%s\"",
                     rv->relname);
            rte->coltypes = lappend_oid(rte->coltypes, att->atttypid);
            rte->coltypmods = lappend_int(rte->coltypmods, att->atttypmod);
            rte->colcollations = lappend_oid(rte->colcollations,
                                             att->attcollation);
        }
    }
 
    /*
     * Set flags and access permissions.
     *
     * ENRs are never checked for access rights, so no need to perform
     * addRTEPermissionInfo().
     */
    rte->lateral = false;
    rte->inh = false;           /* never true for ENRs */
    rte->inFromCl = inFromCl;
 
    /*
     * Add completed RTE to pstate's range table list, so that we know its
     * index.  But we don't add it to the join list --- caller must do that if
     * appropriate.
     */
    pstate->p_rtable = lappend(pstate->p_rtable, rte);
 
    /*
     * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
     * list --- caller must do that if appropriate.
     */
    return buildNSItemFromTupleDesc(rte, list_length(pstate->p_rtable), NULL,
                                    tupdesc);
}

References RangeVar::alias, Alias::aliasname, Assert(), buildNSItemFromTupleDesc(), buildRelationAliases(), RangeTblEntry::colcollations, RangeTblEntry::coltypes, RangeTblEntry::coltypmods, elog(), ENR_NAMED_TUPLESTORE, ENRMetadataGetTupDesc(), RangeTblEntry::enrname, RangeTblEntry::enrtuples, EphemeralNamedRelationMetadataData::enrtuples, EphemeralNamedRelationMetadataData::enrtype, RangeTblEntry::eref, ERROR, get_visible_ENR(), RangeTblEntry::inFromCl, RangeTblEntry::inh, InvalidOid, lappend(), lappend_int(), lappend_oid(), RangeTblEntry::lateral, list_length(), makeAlias(), makeNode, EphemeralNamedRelationMetadataData::name, TupleDescData::natts, NIL, ParseState::p_rtable, RangeTblEntry::relid, EphemeralNamedRelationMetadataData::reliddesc, RangeVar::relname, RTE_NAMEDTUPLESTORE, RangeTblEntry::rtekind, and TupleDescAttr.

Referenced by getNSItemForSpecialRelationTypes().

addRangeTableEntryForFunction()

ParseNamespaceItem* addRangeTableEntryForFunction	(	ParseState *	pstate,
		List *	funcnames,
		List *	funcexprs,
		List *	coldeflists,
		RangeFunction *	rangefunc,
		bool	lateral,
		bool	inFromCl
	)

Definition at line 1735 of file parse_relation.c.

{
    RangeTblEntry *rte = makeNode(RangeTblEntry);
    Alias      *alias = rangefunc->alias;
    Alias      *eref;
    char       *aliasname;
    int         nfuncs = list_length(funcexprs);
    TupleDesc  *functupdescs;
    TupleDesc   tupdesc;
    ListCell   *lc1,
               *lc2,
               *lc3;
    int         i;
    int         j;
    int         funcno;
    int         natts,
                totalatts;
 
    Assert(pstate != NULL);
 
    rte->rtekind = RTE_FUNCTION;
    rte->relid = InvalidOid;
    rte->subquery = NULL;
    rte->functions = NIL;       /* we'll fill this list below */
    rte->funcordinality = rangefunc->ordinality;
    rte->alias = alias;
 
    /*
     * Choose the RTE alias name.  We default to using the first function's
     * name even when there's more than one; which is maybe arguable but beats
     * using something constant like "table".
     */
    if (alias)
        aliasname = alias->aliasname;
    else
        aliasname = linitial(funcnames);
 
    eref = makeAlias(aliasname, NIL);
    rte->eref = eref;
 
    /* Process each function ... */
    functupdescs = (TupleDesc *) palloc(nfuncs * sizeof(TupleDesc));
 
    totalatts = 0;
    funcno = 0;
    forthree(lc1, funcexprs, lc2, funcnames, lc3, coldeflists)
    {
        Node       *funcexpr = (Node *) lfirst(lc1);
        char       *funcname = (char *) lfirst(lc2);
        List       *coldeflist = (List *) lfirst(lc3);
        RangeTblFunction *rtfunc = makeNode(RangeTblFunction);
        TypeFuncClass functypclass;
        Oid         funcrettype;
 
        /* Initialize RangeTblFunction node */
        rtfunc->funcexpr = funcexpr;
        rtfunc->funccolnames = NIL;
        rtfunc->funccoltypes = NIL;
        rtfunc->funccoltypmods = NIL;
        rtfunc->funccolcollations = NIL;
        rtfunc->funcparams = NULL;  /* not set until planning */
 
        /*
         * Now determine if the function returns a simple or composite type.
         */
        functypclass = get_expr_result_type(funcexpr,
                                            &funcrettype,
                                            &tupdesc);
 
        /*
         * A coldeflist is required if the function returns RECORD and hasn't
         * got a predetermined record type, and is prohibited otherwise.  This
         * can be a bit confusing, so we expend some effort on delivering a
         * relevant error message.
         */
        if (coldeflist != NIL)
        {
            switch (functypclass)
            {
                case TYPEFUNC_RECORD:
                    /* ok */
                    break;
                case TYPEFUNC_COMPOSITE:
                case TYPEFUNC_COMPOSITE_DOMAIN:
 
                    /*
                     * If the function's raw result type is RECORD, we must
                     * have resolved it using its OUT parameters.  Otherwise,
                     * it must have a named composite type.
                     */
                    if (exprType(funcexpr) == RECORDOID)
                        ereport(ERROR,
                                (errcode(ERRCODE_SYNTAX_ERROR),
                                 errmsg("a column definition list is redundant for a function with OUT parameters"),
                                 parser_errposition(pstate,
                                                    exprLocation((Node *) coldeflist))));
                    else
                        ereport(ERROR,
                                (errcode(ERRCODE_SYNTAX_ERROR),
                                 errmsg("a column definition list is redundant for a function returning a named composite type"),
                                 parser_errposition(pstate,
                                                    exprLocation((Node *) coldeflist))));
                    break;
                default:
                    ereport(ERROR,
                            (errcode(ERRCODE_SYNTAX_ERROR),
                             errmsg("a column definition list is only allowed for functions returning \"record\""),
                             parser_errposition(pstate,
                                                exprLocation((Node *) coldeflist))));
                    break;
            }
        }
        else
        {
            if (functypclass == TYPEFUNC_RECORD)
                ereport(ERROR,
                        (errcode(ERRCODE_SYNTAX_ERROR),
                         errmsg("a column definition list is required for functions returning \"record\""),
                         parser_errposition(pstate, exprLocation(funcexpr))));
        }
 
        if (functypclass == TYPEFUNC_COMPOSITE ||
            functypclass == TYPEFUNC_COMPOSITE_DOMAIN)
        {
            /* Composite data type, e.g. a table's row type */
            Assert(tupdesc);
        }
        else if (functypclass == TYPEFUNC_SCALAR)
        {
            /* Base data type, i.e. scalar */
            tupdesc = CreateTemplateTupleDesc(1);
            TupleDescInitEntry(tupdesc,
                               (AttrNumber) 1,
                               chooseScalarFunctionAlias(funcexpr, funcname,
                                                         alias, nfuncs),
                               funcrettype,
                               exprTypmod(funcexpr),
                               0);
            TupleDescInitEntryCollation(tupdesc,
                                        (AttrNumber) 1,
                                        exprCollation(funcexpr));
        }
        else if (functypclass == TYPEFUNC_RECORD)
        {
            ListCell   *col;
 
            /*
             * Use the column definition list to construct a tupdesc and fill
             * in the RangeTblFunction's lists.  Limit number of columns to
             * MaxHeapAttributeNumber, because CheckAttributeNamesTypes will.
             */
            if (list_length(coldeflist) > MaxHeapAttributeNumber)
                ereport(ERROR,
                        (errcode(ERRCODE_TOO_MANY_COLUMNS),
                         errmsg("column definition lists can have at most %d entries",
                                MaxHeapAttributeNumber),
                         parser_errposition(pstate,
                                            exprLocation((Node *) coldeflist))));
            tupdesc = CreateTemplateTupleDesc(list_length(coldeflist));
            i = 1;
            foreach(col, coldeflist)
            {
                ColumnDef  *n = (ColumnDef *) lfirst(col);
                char       *attrname;
                Oid         attrtype;
                int32       attrtypmod;
                Oid         attrcollation;
 
                attrname = n->colname;
                if (n->typeName->setof)
                    ereport(ERROR,
                            (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
                             errmsg("column \"%s\" cannot be declared SETOF",
                                    attrname),
                             parser_errposition(pstate, n->location)));
                typenameTypeIdAndMod(pstate, n->typeName,
                                     &attrtype, &attrtypmod);
                attrcollation = GetColumnDefCollation(pstate, n, attrtype);
                TupleDescInitEntry(tupdesc,
                                   (AttrNumber) i,
                                   attrname,
                                   attrtype,
                                   attrtypmod,
                                   0);
                TupleDescInitEntryCollation(tupdesc,
                                            (AttrNumber) i,
                                            attrcollation);
                rtfunc->funccolnames = lappend(rtfunc->funccolnames,
                                               makeString(pstrdup(attrname)));
                rtfunc->funccoltypes = lappend_oid(rtfunc->funccoltypes,
                                                   attrtype);
                rtfunc->funccoltypmods = lappend_int(rtfunc->funccoltypmods,
                                                     attrtypmod);
                rtfunc->funccolcollations = lappend_oid(rtfunc->funccolcollations,
                                                        attrcollation);
 
                i++;
            }
 
            /*
             * Ensure that the coldeflist defines a legal set of names (no
             * duplicates, but we needn't worry about system column names) and
             * datatypes.  Although we mostly can't allow pseudo-types, it
             * seems safe to allow RECORD and RECORD[], since values within
             * those type classes are self-identifying at runtime, and the
             * coldeflist doesn't represent anything that will be visible to
             * other sessions.
             */
            CheckAttributeNamesTypes(tupdesc, RELKIND_COMPOSITE_TYPE,
                                     CHKATYPE_ANYRECORD);
        }
        else
            ereport(ERROR,
                    (errcode(ERRCODE_DATATYPE_MISMATCH),
                     errmsg("function \"%s\" in FROM has unsupported return type %s",
                            funcname, format_type_be(funcrettype)),
                     parser_errposition(pstate, exprLocation(funcexpr))));
 
        /* Finish off the RangeTblFunction and add it to the RTE's list */
        rtfunc->funccolcount = tupdesc->natts;
        rte->functions = lappend(rte->functions, rtfunc);
 
        /* Save the tupdesc for use below */
        functupdescs[funcno] = tupdesc;
        totalatts += tupdesc->natts;
        funcno++;
    }
 
    /*
     * If there's more than one function, or we want an ordinality column, we
     * have to produce a merged tupdesc.
     */
    if (nfuncs > 1 || rangefunc->ordinality)
    {
        if (rangefunc->ordinality)
            totalatts++;
 
        /* Disallow more columns than will fit in a tuple */
        if (totalatts > MaxTupleAttributeNumber)
            ereport(ERROR,
                    (errcode(ERRCODE_TOO_MANY_COLUMNS),
                     errmsg("functions in FROM can return at most %d columns",
                            MaxTupleAttributeNumber),
                     parser_errposition(pstate,
                                        exprLocation((Node *) funcexprs))));
 
        /* Merge the tuple descs of each function into a composite one */
        tupdesc = CreateTemplateTupleDesc(totalatts);
        natts = 0;
        for (i = 0; i < nfuncs; i++)
        {
            for (j = 1; j <= functupdescs[i]->natts; j++)
                TupleDescCopyEntry(tupdesc, ++natts, functupdescs[i], j);
        }
 
        /* Add the ordinality column if needed */
        if (rangefunc->ordinality)
        {
            TupleDescInitEntry(tupdesc,
                               (AttrNumber) ++natts,
                               "ordinality",
                               INT8OID,
                               -1,
                               0);
            /* no need to set collation */
        }
 
        Assert(natts == totalatts);
    }
    else
    {
        /* We can just use the single function's tupdesc as-is */
        tupdesc = functupdescs[0];
    }
 
    /* Use the tupdesc while assigning column aliases for the RTE */
    buildRelationAliases(tupdesc, alias, eref);
 
    /*
     * Set flags and access permissions.
     *
     * Functions are never checked for access rights (at least, not by
     * ExecCheckPermissions()), so no need to perform addRTEPermissionInfo().
     */
    rte->lateral = lateral;
    rte->inh = false;           /* never true for functions */
    rte->inFromCl = inFromCl;
 
    /*
     * Add completed RTE to pstate's range table list, so that we know its
     * index.  But we don't add it to the join list --- caller must do that if
     * appropriate.
     */
    pstate->p_rtable = lappend(pstate->p_rtable, rte);
 
    /*
     * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
     * list --- caller must do that if appropriate.
     */
    return buildNSItemFromTupleDesc(rte, list_length(pstate->p_rtable), NULL,
                                    tupdesc);
}

References RangeFunction::alias, RangeTblEntry::alias, Alias::aliasname, Assert(), buildNSItemFromTupleDesc(), buildRelationAliases(), CheckAttributeNamesTypes(), CHKATYPE_ANYRECORD, chooseScalarFunctionAlias(), ColumnDef::colname, CreateTemplateTupleDesc(), RangeTblEntry::eref, ereport, errcode(), errmsg(), ERROR, exprCollation(), exprLocation(), exprType(), exprTypmod(), format_type_be(), forthree, RangeTblFunction::funcexpr, funcname, RangeTblEntry::funcordinality, RangeTblEntry::functions, get_expr_result_type(), GetColumnDefCollation(), i, RangeTblEntry::inFromCl, RangeTblEntry::inh, InvalidOid, j, lappend(), lappend_int(), lappend_oid(), RangeTblEntry::lateral, lfirst, linitial, list_length(), ColumnDef::location, makeAlias(), makeNode, makeString(), MaxHeapAttributeNumber, MaxTupleAttributeNumber, TupleDescData::natts, NIL, RangeFunction::ordinality, ParseState::p_rtable, palloc(), parser_errposition(), pstrdup(), RangeTblEntry::relid, RTE_FUNCTION, RangeTblEntry::rtekind, TypeName::setof, RangeTblEntry::subquery, TupleDescCopyEntry(), TupleDescInitEntry(), TupleDescInitEntryCollation(), TYPEFUNC_COMPOSITE, TYPEFUNC_COMPOSITE_DOMAIN, TYPEFUNC_RECORD, TYPEFUNC_SCALAR, ColumnDef::typeName, and typenameTypeIdAndMod().

Referenced by transformRangeFunction().

addRangeTableEntryForJoin()

ParseNamespaceItem* addRangeTableEntryForJoin	(	ParseState *	pstate,
		List *	colnames,
		ParseNamespaceColumn *	nscolumns,
		JoinType	jointype,
		int	nummergedcols,
		List *	aliasvars,
		List *	leftcols,
		List *	rightcols,
		Alias *	join_using_alias,
		Alias *	alias,
		bool	inFromCl
	)

Definition at line 2220 of file parse_relation.c.

{
    RangeTblEntry *rte = makeNode(RangeTblEntry);
    Alias      *eref;
    int         numaliases;
    ParseNamespaceItem *nsitem;
 
    Assert(pstate != NULL);
 
    /*
     * Fail if join has too many columns --- we must be able to reference any
     * of the columns with an AttrNumber.
     */
    if (list_length(aliasvars) > MaxAttrNumber)
        ereport(ERROR,
                (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
                 errmsg("joins can have at most %d columns",
                        MaxAttrNumber)));
 
    rte->rtekind = RTE_JOIN;
    rte->relid = InvalidOid;
    rte->subquery = NULL;
    rte->jointype = jointype;
    rte->joinmergedcols = nummergedcols;
    rte->joinaliasvars = aliasvars;
    rte->joinleftcols = leftcols;
    rte->joinrightcols = rightcols;
    rte->join_using_alias = join_using_alias;
    rte->alias = alias;
 
    eref = alias ? copyObject(alias) : makeAlias("unnamed_join", NIL);
    numaliases = list_length(eref->colnames);
 
    /* fill in any unspecified alias columns */
    if (numaliases < list_length(colnames))
        eref->colnames = list_concat(eref->colnames,
                                     list_copy_tail(colnames, numaliases));
 
    if (numaliases > list_length(colnames))
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
                 errmsg("join expression \"%s\" has %d columns available but %d columns specified",
                        eref->aliasname, list_length(colnames), numaliases)));
 
    rte->eref = eref;
 
    /*
     * Set flags and access permissions.
     *
     * Joins are never checked for access rights, so no need to perform
     * addRTEPermissionInfo().
     */
    rte->lateral = false;
    rte->inh = false;           /* never true for joins */
    rte->inFromCl = inFromCl;
 
    /*
     * Add completed RTE to pstate's range table list, so that we know its
     * index.  But we don't add it to the join list --- caller must do that if
     * appropriate.
     */
    pstate->p_rtable = lappend(pstate->p_rtable, rte);
 
    /*
     * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
     * list --- caller must do that if appropriate.
     */
    nsitem = (ParseNamespaceItem *) palloc(sizeof(ParseNamespaceItem));
    nsitem->p_names = rte->eref;
    nsitem->p_rte = rte;
    nsitem->p_perminfo = NULL;
    nsitem->p_rtindex = list_length(pstate->p_rtable);
    nsitem->p_nscolumns = nscolumns;
    /* set default visibility flags; might get changed later */
    nsitem->p_rel_visible = true;
    nsitem->p_cols_visible = true;
    nsitem->p_lateral_only = false;
    nsitem->p_lateral_ok = true;
 
    return nsitem;
}

References RangeTblEntry::alias, Alias::aliasname, Assert(), Alias::colnames, copyObject, RangeTblEntry::eref, ereport, errcode(), errmsg(), ERROR, RangeTblEntry::inFromCl, RangeTblEntry::inh, InvalidOid, RangeTblEntry::join_using_alias, RangeTblEntry::joinaliasvars, RangeTblEntry::joinleftcols, RangeTblEntry::joinmergedcols, RangeTblEntry::joinrightcols, RangeTblEntry::jointype, lappend(), RangeTblEntry::lateral, list_concat(), list_copy_tail(), list_length(), makeAlias(), makeNode, MaxAttrNumber, NIL, ParseNamespaceItem::p_cols_visible, ParseNamespaceItem::p_lateral_ok, ParseNamespaceItem::p_lateral_only, ParseNamespaceItem::p_names, ParseNamespaceItem::p_nscolumns, ParseNamespaceItem::p_perminfo, ParseNamespaceItem::p_rel_visible, ParseState::p_rtable, ParseNamespaceItem::p_rte, ParseNamespaceItem::p_rtindex, palloc(), RangeTblEntry::relid, RTE_JOIN, RangeTblEntry::rtekind, and RangeTblEntry::subquery.

Referenced by transformFromClauseItem(), and transformSetOperationStmt().

addRangeTableEntryForRelation()

ParseNamespaceItem* addRangeTableEntryForRelation	(	ParseState *	pstate,
		Relation	rel,
		int	lockmode,
		Alias *	alias,
		bool	inh,
		bool	inFromCl
	)

Definition at line 1567 of file parse_relation.c.

{
    RangeTblEntry *rte = makeNode(RangeTblEntry);
    RTEPermissionInfo *perminfo;
    char       *refname = alias ? alias->aliasname : RelationGetRelationName(rel);
 
    Assert(pstate != NULL);
 
    Assert(lockmode == AccessShareLock ||
           lockmode == RowShareLock ||
           lockmode == RowExclusiveLock);
    Assert(CheckRelationLockedByMe(rel, lockmode, true));
 
    rte->rtekind = RTE_RELATION;
    rte->alias = alias;
    rte->relid = RelationGetRelid(rel);
    rte->relkind = rel->rd_rel->relkind;
    rte->rellockmode = lockmode;
 
    /*
     * Build the list of effective column names using user-supplied aliases
     * and/or actual column names.
     */
    rte->eref = makeAlias(refname, NIL);
    buildRelationAliases(rel->rd_att, alias, rte->eref);
 
    /*
     * Set flags and initialize access permissions.
     *
     * The initial default on access checks is always check-for-READ-access,
     * which is the right thing for all except target tables.
     */
    rte->lateral = false;
    rte->inh = inh;
    rte->inFromCl = inFromCl;
 
    perminfo = addRTEPermissionInfo(&pstate->p_rteperminfos, rte);
    perminfo->requiredPerms = ACL_SELECT;
 
    /*
     * Add completed RTE to pstate's range table list, so that we know its
     * index.  But we don't add it to the join list --- caller must do that if
     * appropriate.
     */
    pstate->p_rtable = lappend(pstate->p_rtable, rte);
 
    /*
     * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
     * list --- caller must do that if appropriate.
     */
    return buildNSItemFromTupleDesc(rte, list_length(pstate->p_rtable),
                                    perminfo, rel->rd_att);
}

References AccessShareLock, ACL_SELECT, addRTEPermissionInfo(), RangeTblEntry::alias, Alias::aliasname, Assert(), buildNSItemFromTupleDesc(), buildRelationAliases(), CheckRelationLockedByMe(), RangeTblEntry::eref, RangeTblEntry::inFromCl, RangeTblEntry::inh, lappend(), RangeTblEntry::lateral, list_length(), makeAlias(), makeNode, NIL, ParseState::p_rtable, ParseState::p_rteperminfos, RelationData::rd_att, RelationData::rd_rel, RelationGetRelationName, RelationGetRelid, RangeTblEntry::relid, RangeTblEntry::relkind, RangeTblEntry::rellockmode, RTEPermissionInfo::requiredPerms, RowExclusiveLock, RowShareLock, RTE_RELATION, and RangeTblEntry::rtekind.

Referenced by AddRelationNewConstraints(), AlterPolicy(), copy_table(), CreatePolicy(), CreateTriggerFiringOn(), DefineRelation(), DoCopy(), rewriteTargetView(), setTargetTable(), test_rls_hooks_permissive(), test_rls_hooks_restrictive(), transformAlterTableStmt(), transformIndexStmt(), transformOnConflictClause(), transformPartitionSpec(), TransformPubWhereClauses(), transformRuleStmt(), and transformStatsStmt().

addRangeTableEntryForSubquery()

ParseNamespaceItem* addRangeTableEntryForSubquery	(	ParseState *	pstate,
		Query *	subquery,
		Alias *	alias,
		bool	lateral,
		bool	inFromCl
	)

Definition at line 1638 of file parse_relation.c.

{
    RangeTblEntry *rte = makeNode(RangeTblEntry);
    Alias      *eref;
    int         numaliases;
    List       *coltypes,
               *coltypmods,
               *colcollations;
    int         varattno;
    ListCell   *tlistitem;
    ParseNamespaceItem *nsitem;
 
    Assert(pstate != NULL);
 
    rte->rtekind = RTE_SUBQUERY;
    rte->subquery = subquery;
    rte->alias = alias;
 
    eref = alias ? copyObject(alias) : makeAlias("unnamed_subquery", NIL);
    numaliases = list_length(eref->colnames);
 
    /* fill in any unspecified alias columns, and extract column type info */
    coltypes = coltypmods = colcollations = NIL;
    varattno = 0;
    foreach(tlistitem, subquery->targetList)
    {
        TargetEntry *te = (TargetEntry *) lfirst(tlistitem);
 
        if (te->resjunk)
            continue;
        varattno++;
        Assert(varattno == te->resno);
        if (varattno > numaliases)
        {
            char       *attrname;
 
            attrname = pstrdup(te->resname);
            eref->colnames = lappend(eref->colnames, makeString(attrname));
        }
        coltypes = lappend_oid(coltypes,
                               exprType((Node *) te->expr));
        coltypmods = lappend_int(coltypmods,
                                 exprTypmod((Node *) te->expr));
        colcollations = lappend_oid(colcollations,
                                    exprCollation((Node *) te->expr));
    }
    if (varattno < numaliases)
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
                 errmsg("table \"%s\" has %d columns available but %d columns specified",
                        eref->aliasname, varattno, numaliases)));
 
    rte->eref = eref;
 
    /*
     * Set flags.
     *
     * Subqueries are never checked for access rights, so no need to perform
     * addRTEPermissionInfo().
     */
    rte->lateral = lateral;
    rte->inh = false;           /* never true for subqueries */
    rte->inFromCl = inFromCl;
 
    /*
     * Add completed RTE to pstate's range table list, so that we know its
     * index.  But we don't add it to the join list --- caller must do that if
     * appropriate.
     */
    pstate->p_rtable = lappend(pstate->p_rtable, rte);
 
    /*
     * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
     * list --- caller must do that if appropriate.
     */
    nsitem = buildNSItemFromLists(rte, list_length(pstate->p_rtable),
                                  coltypes, coltypmods, colcollations);
 
    /*
     * Mark it visible as a relation name only if it had a user-written alias.
     */
    nsitem->p_rel_visible = (alias != NULL);
 
    return nsitem;
}

References RangeTblEntry::alias, Alias::aliasname, Assert(), buildNSItemFromLists(), Alias::colnames, copyObject, RangeTblEntry::eref, ereport, errcode(), errmsg(), ERROR, TargetEntry::expr, exprCollation(), exprType(), exprTypmod(), RangeTblEntry::inFromCl, RangeTblEntry::inh, lappend(), lappend_int(), lappend_oid(), RangeTblEntry::lateral, lfirst, list_length(), makeAlias(), makeNode, makeString(), NIL, ParseNamespaceItem::p_rel_visible, ParseState::p_rtable, pstrdup(), TargetEntry::resno, RTE_SUBQUERY, RangeTblEntry::rtekind, RangeTblEntry::subquery, and Query::targetList.

Referenced by convert_ANY_sublink_to_join(), transformInsertStmt(), transformRangeSubselect(), and transformSetOperationTree().

addRangeTableEntryForTableFunc()

ParseNamespaceItem* addRangeTableEntryForTableFunc	(	ParseState *	pstate,
		TableFunc *	tf,
		Alias *	alias,
		bool	lateral,
		bool	inFromCl
	)

Definition at line 2051 of file parse_relation.c.

{
    RangeTblEntry *rte = makeNode(RangeTblEntry);
    char       *refname;
    Alias      *eref;
    int         numaliases;
 
    Assert(pstate != NULL);
 
    /* Disallow more columns than will fit in a tuple */
    if (list_length(tf->colnames) > MaxTupleAttributeNumber)
        ereport(ERROR,
                (errcode(ERRCODE_TOO_MANY_COLUMNS),
                 errmsg("functions in FROM can return at most %d columns",
                        MaxTupleAttributeNumber),
                 parser_errposition(pstate,
                                    exprLocation((Node *) tf))));
    Assert(list_length(tf->coltypes) == list_length(tf->colnames));
    Assert(list_length(tf->coltypmods) == list_length(tf->colnames));
    Assert(list_length(tf->colcollations) == list_length(tf->colnames));
 
    refname = alias ? alias->aliasname : pstrdup("xmltable");
 
    rte->rtekind = RTE_TABLEFUNC;
    rte->relid = InvalidOid;
    rte->subquery = NULL;
    rte->tablefunc = tf;
    rte->coltypes = tf->coltypes;
    rte->coltypmods = tf->coltypmods;
    rte->colcollations = tf->colcollations;
    rte->alias = alias;
 
    eref = alias ? copyObject(alias) : makeAlias(refname, NIL);
    numaliases = list_length(eref->colnames);
 
    /* fill in any unspecified alias columns */
    if (numaliases < list_length(tf->colnames))
        eref->colnames = list_concat(eref->colnames,
                                     list_copy_tail(tf->colnames, numaliases));
 
    if (numaliases > list_length(tf->colnames))
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
                 errmsg("%s function has %d columns available but %d columns specified",
                        "XMLTABLE",
                        list_length(tf->colnames), numaliases)));
 
    rte->eref = eref;
 
    /*
     * Set flags and access permissions.
     *
     * Tablefuncs are never checked for access rights (at least, not by
     * ExecCheckPermissions()), so no need to perform addRTEPermissionInfo().
     */
    rte->lateral = lateral;
    rte->inh = false;           /* never true for tablefunc RTEs */
    rte->inFromCl = inFromCl;
 
    /*
     * Add completed RTE to pstate's range table list, so that we know its
     * index.  But we don't add it to the join list --- caller must do that if
     * appropriate.
     */
    pstate->p_rtable = lappend(pstate->p_rtable, rte);
 
    /*
     * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
     * list --- caller must do that if appropriate.
     */
    return buildNSItemFromLists(rte, list_length(pstate->p_rtable),
                                rte->coltypes, rte->coltypmods,
                                rte->colcollations);
}

References RangeTblEntry::alias, Alias::aliasname, Assert(), buildNSItemFromLists(), RangeTblEntry::colcollations, Alias::colnames, RangeTblEntry::coltypes, RangeTblEntry::coltypmods, copyObject, RangeTblEntry::eref, ereport, errcode(), errmsg(), ERROR, exprLocation(), RangeTblEntry::inFromCl, RangeTblEntry::inh, InvalidOid, lappend(), RangeTblEntry::lateral, list_concat(), list_copy_tail(), list_length(), makeAlias(), makeNode, MaxTupleAttributeNumber, NIL, ParseState::p_rtable, parser_errposition(), pstrdup(), RangeTblEntry::relid, RTE_TABLEFUNC, RangeTblEntry::rtekind, RangeTblEntry::subquery, and RangeTblEntry::tablefunc.

Referenced by transformRangeTableFunc().

addRangeTableEntryForValues()

ParseNamespaceItem* addRangeTableEntryForValues	(	ParseState *	pstate,
		List *	exprs,
		List *	coltypes,
		List *	coltypmods,
		List *	colcollations,
		Alias *	alias,
		bool	lateral,
		bool	inFromCl
	)

Definition at line 2137 of file parse_relation.c.

{
    RangeTblEntry *rte = makeNode(RangeTblEntry);
    char       *refname = alias ? alias->aliasname : pstrdup("*VALUES*");
    Alias      *eref;
    int         numaliases;
    int         numcolumns;
 
    Assert(pstate != NULL);
 
    rte->rtekind = RTE_VALUES;
    rte->relid = InvalidOid;
    rte->subquery = NULL;
    rte->values_lists = exprs;
    rte->coltypes = coltypes;
    rte->coltypmods = coltypmods;
    rte->colcollations = colcollations;
    rte->alias = alias;
 
    eref = alias ? copyObject(alias) : makeAlias(refname, NIL);
 
    /* fill in any unspecified alias columns */
    numcolumns = list_length((List *) linitial(exprs));
    numaliases = list_length(eref->colnames);
    while (numaliases < numcolumns)
    {
        char        attrname[64];
 
        numaliases++;
        snprintf(attrname, sizeof(attrname), "column%d", numaliases);
        eref->colnames = lappend(eref->colnames,
                                 makeString(pstrdup(attrname)));
    }
    if (numcolumns < numaliases)
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
                 errmsg("VALUES lists \"%s\" have %d columns available but %d columns specified",
                        refname, numcolumns, numaliases)));
 
    rte->eref = eref;
 
    /*
     * Set flags and access permissions.
     *
     * Subqueries are never checked for access rights, so no need to perform
     * addRTEPermissionInfo().
     */
    rte->lateral = lateral;
    rte->inh = false;           /* never true for values RTEs */
    rte->inFromCl = inFromCl;
 
    /*
     * Add completed RTE to pstate's range table list, so that we know its
     * index.  But we don't add it to the join list --- caller must do that if
     * appropriate.
     */
    pstate->p_rtable = lappend(pstate->p_rtable, rte);
 
    /*
     * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
     * list --- caller must do that if appropriate.
     */
    return buildNSItemFromLists(rte, list_length(pstate->p_rtable),
                                rte->coltypes, rte->coltypmods,
                                rte->colcollations);
}

References RangeTblEntry::alias, Alias::aliasname, Assert(), buildNSItemFromLists(), RangeTblEntry::colcollations, Alias::colnames, RangeTblEntry::coltypes, RangeTblEntry::coltypmods, copyObject, RangeTblEntry::eref, ereport, errcode(), errmsg(), ERROR, RangeTblEntry::inFromCl, RangeTblEntry::inh, InvalidOid, lappend(), RangeTblEntry::lateral, linitial, list_length(), makeAlias(), makeNode, makeString(), NIL, ParseState::p_rtable, pstrdup(), RangeTblEntry::relid, RTE_VALUES, RangeTblEntry::rtekind, snprintf, RangeTblEntry::subquery, and RangeTblEntry::values_lists.

Referenced by transformValuesClause().

addRTEPermissionInfo()

RTEPermissionInfo* addRTEPermissionInfo	(	List **	rteperminfos,
		RangeTblEntry *	rte
	)

Definition at line 3871 of file parse_relation.c.

{
    RTEPermissionInfo *perminfo;
 
    Assert(OidIsValid(rte->relid));
    Assert(rte->perminfoindex == 0);
 
    /* Nope, so make one and add to the list. */
    perminfo = makeNode(RTEPermissionInfo);
    perminfo->relid = rte->relid;
    perminfo->inh = rte->inh;
    /* Other information is set by fetching the node as and where needed. */
 
    *rteperminfos = lappend(*rteperminfos, perminfo);
 
    /* Note its index (1-based!) */
    rte->perminfoindex = list_length(*rteperminfos);
 
    return perminfo;
}

References Assert(), RangeTblEntry::inh, RTEPermissionInfo::inh, lappend(), list_length(), makeNode, OidIsValid, RangeTblEntry::perminfoindex, RangeTblEntry::relid, and RTEPermissionInfo::relid.

Referenced by add_rte_to_flat_rtable(), addRangeTableEntry(), addRangeTableEntryForRelation(), create_edata_for_relation(), create_estate_for_relation(), plan_cluster_use_sort(), plan_create_index_workers(), and rewriteTargetView().

attnameAttNum()

int attnameAttNum	(	Relation	rd,
		const char *	attname,
		bool	sysColOK
	)

Definition at line 3480 of file parse_relation.c.

{
    int         i;
 
    for (i = 0; i < RelationGetNumberOfAttributes(rd); i++)
    {
        Form_pg_attribute att = TupleDescAttr(rd->rd_att, i);
 
        if (namestrcmp(&(att->attname), attname) == 0 && !att->attisdropped)
            return i + 1;
    }
 
    if (sysColOK)
    {
        if ((i = specialAttNum(attname)) != InvalidAttrNumber)
            return i;
    }
 
    /* on failure */
    return InvalidAttrNumber;
}

References attname, i, InvalidAttrNumber, namestrcmp(), RelationData::rd_att, RelationGetNumberOfAttributes, specialAttNum(), and TupleDescAttr.

Referenced by checkInsertTargets(), CreateTriggerFiringOn(), do_analyze_rel(), and transformUpdateTargetList().

attnumAttName()

const NameData* attnumAttName	(	Relation	rd,
		int	attid
	)

Definition at line 3530 of file parse_relation.c.

{
    if (attid <= 0)
    {
        const FormData_pg_attribute *sysatt;
 
        sysatt = SystemAttributeDefinition(attid);
        return &sysatt->attname;
    }
    if (attid > rd->rd_att->natts)
        elog(ERROR, "invalid attribute number %d", attid);
    return &TupleDescAttr(rd->rd_att, attid - 1)->attname;
}

References elog(), ERROR, FormData_pg_attribute, TupleDescData::natts, RelationData::rd_att, SystemAttributeDefinition(), and TupleDescAttr.

Referenced by transformFkeyGetPrimaryKey().

attnumCollationId()

Oid attnumCollationId	(	Relation	rd,
		int	attid
	)

Definition at line 3572 of file parse_relation.c.

{
    if (attid <= 0)
    {
        /* All system attributes are of noncollatable types. */
        return InvalidOid;
    }
    if (attid > rd->rd_att->natts)
        elog(ERROR, "invalid attribute number %d", attid);
    return TupleDescAttr(rd->rd_att, attid - 1)->attcollation;
}

References elog(), ERROR, InvalidOid, TupleDescData::natts, RelationData::rd_att, and TupleDescAttr.

attnumTypeId()

Oid attnumTypeId	(	Relation	rd,
		int	attid
	)

Definition at line 3552 of file parse_relation.c.

{
    if (attid <= 0)
    {
        const FormData_pg_attribute *sysatt;
 
        sysatt = SystemAttributeDefinition(attid);
        return sysatt->atttypid;
    }
    if (attid > rd->rd_att->natts)
        elog(ERROR, "invalid attribute number %d", attid);
    return TupleDescAttr(rd->rd_att, attid - 1)->atttypid;
}

References elog(), ERROR, FormData_pg_attribute, TupleDescData::natts, RelationData::rd_att, SystemAttributeDefinition(), and TupleDescAttr.

Referenced by transformAssignedExpr(), and transformFkeyGetPrimaryKey().

buildNSItemFromLists()

static ParseNamespaceItem* buildNSItemFromLists ( RangeTblEntry *  rte, Index  rtindex, List *  coltypes, List *  coltypmods, List *  colcollations  )

static

Definition at line 1354 of file parse_relation.c.

{
    ParseNamespaceItem *nsitem;
    ParseNamespaceColumn *nscolumns;
    int         maxattrs = list_length(coltypes);
    int         varattno;
    ListCell   *lct;
    ListCell   *lcm;
    ListCell   *lcc;
 
    /* colnames must have the same number of entries as the nsitem */
    Assert(maxattrs == list_length(rte->eref->colnames));
 
    Assert(maxattrs == list_length(coltypmods));
    Assert(maxattrs == list_length(colcollations));
 
    /* extract per-column data from the lists */
    nscolumns = (ParseNamespaceColumn *)
        palloc0(maxattrs * sizeof(ParseNamespaceColumn));
 
    varattno = 0;
    forthree(lct, coltypes,
             lcm, coltypmods,
             lcc, colcollations)
    {
        nscolumns[varattno].p_varno = rtindex;
        nscolumns[varattno].p_varattno = varattno + 1;
        nscolumns[varattno].p_vartype = lfirst_oid(lct);
        nscolumns[varattno].p_vartypmod = lfirst_int(lcm);
        nscolumns[varattno].p_varcollid = lfirst_oid(lcc);
        nscolumns[varattno].p_varnosyn = rtindex;
        nscolumns[varattno].p_varattnosyn = varattno + 1;
        varattno++;
    }
 
    /* ... and build the nsitem */
    nsitem = (ParseNamespaceItem *) palloc(sizeof(ParseNamespaceItem));
    nsitem->p_names = rte->eref;
    nsitem->p_rte = rte;
    nsitem->p_rtindex = rtindex;
    nsitem->p_perminfo = NULL;
    nsitem->p_nscolumns = nscolumns;
    /* set default visibility flags; might get changed later */
    nsitem->p_rel_visible = true;
    nsitem->p_cols_visible = true;
    nsitem->p_lateral_only = false;
    nsitem->p_lateral_ok = true;
 
    return nsitem;
}

References Assert(), Alias::colnames, RangeTblEntry::eref, forthree, lfirst_int, lfirst_oid, list_length(), ParseNamespaceItem::p_cols_visible, ParseNamespaceItem::p_lateral_ok, ParseNamespaceItem::p_lateral_only, ParseNamespaceItem::p_names, ParseNamespaceItem::p_nscolumns, ParseNamespaceItem::p_perminfo, ParseNamespaceItem::p_rel_visible, ParseNamespaceItem::p_rte, ParseNamespaceItem::p_rtindex, ParseNamespaceColumn::p_varattno, ParseNamespaceColumn::p_varattnosyn, ParseNamespaceColumn::p_varcollid, ParseNamespaceColumn::p_varno, ParseNamespaceColumn::p_varnosyn, ParseNamespaceColumn::p_vartype, ParseNamespaceColumn::p_vartypmod, palloc(), and palloc0().

Referenced by addRangeTableEntryForCTE(), addRangeTableEntryForSubquery(), addRangeTableEntryForTableFunc(), and addRangeTableEntryForValues().

buildNSItemFromTupleDesc()

static ParseNamespaceItem* buildNSItemFromTupleDesc ( RangeTblEntry *  rte, Index  rtindex, RTEPermissionInfo *  perminfo, TupleDesc  tupdesc  )

static

Definition at line 1294 of file parse_relation.c.

{
    ParseNamespaceItem *nsitem;
    ParseNamespaceColumn *nscolumns;
    int         maxattrs = tupdesc->natts;
    int         varattno;
 
    /* colnames must have the same number of entries as the nsitem */
    Assert(maxattrs == list_length(rte->eref->colnames));
 
    /* extract per-column data from the tupdesc */
    nscolumns = (ParseNamespaceColumn *)
        palloc0(maxattrs * sizeof(ParseNamespaceColumn));
 
    for (varattno = 0; varattno < maxattrs; varattno++)
    {
        Form_pg_attribute attr = TupleDescAttr(tupdesc, varattno);
 
        /* For a dropped column, just leave the entry as zeroes */
        if (attr->attisdropped)
            continue;
 
        nscolumns[varattno].p_varno = rtindex;
        nscolumns[varattno].p_varattno = varattno + 1;
        nscolumns[varattno].p_vartype = attr->atttypid;
        nscolumns[varattno].p_vartypmod = attr->atttypmod;
        nscolumns[varattno].p_varcollid = attr->attcollation;
        nscolumns[varattno].p_varnosyn = rtindex;
        nscolumns[varattno].p_varattnosyn = varattno + 1;
    }
 
    /* ... and build the nsitem */
    nsitem = (ParseNamespaceItem *) palloc(sizeof(ParseNamespaceItem));
    nsitem->p_names = rte->eref;
    nsitem->p_rte = rte;
    nsitem->p_rtindex = rtindex;
    nsitem->p_perminfo = perminfo;
    nsitem->p_nscolumns = nscolumns;
    /* set default visibility flags; might get changed later */
    nsitem->p_rel_visible = true;
    nsitem->p_cols_visible = true;
    nsitem->p_lateral_only = false;
    nsitem->p_lateral_ok = true;
 
    return nsitem;
}

References Assert(), Alias::colnames, RangeTblEntry::eref, list_length(), TupleDescData::natts, ParseNamespaceItem::p_cols_visible, ParseNamespaceItem::p_lateral_ok, ParseNamespaceItem::p_lateral_only, ParseNamespaceItem::p_names, ParseNamespaceItem::p_nscolumns, ParseNamespaceItem::p_perminfo, ParseNamespaceItem::p_rel_visible, ParseNamespaceItem::p_rte, ParseNamespaceItem::p_rtindex, ParseNamespaceColumn::p_varattno, ParseNamespaceColumn::p_varattnosyn, ParseNamespaceColumn::p_varcollid, ParseNamespaceColumn::p_varno, ParseNamespaceColumn::p_varnosyn, ParseNamespaceColumn::p_vartype, ParseNamespaceColumn::p_vartypmod, palloc(), palloc0(), and TupleDescAttr.

Referenced by addRangeTableEntry(), addRangeTableEntryForENR(), addRangeTableEntryForFunction(), and addRangeTableEntryForRelation().

buildRelationAliases()

static void buildRelationAliases ( TupleDesc  tupdesc, Alias *  alias, Alias *  eref  )

static

Definition at line 1177 of file parse_relation.c.

{
    int         maxattrs = tupdesc->natts;
    List       *aliaslist;
    ListCell   *aliaslc;
    int         numaliases;
    int         varattno;
    int         numdropped = 0;
 
    Assert(eref->colnames == NIL);
 
    if (alias)
    {
        aliaslist = alias->colnames;
        aliaslc = list_head(aliaslist);
        numaliases = list_length(aliaslist);
        /* We'll rebuild the alias colname list */
        alias->colnames = NIL;
    }
    else
    {
        aliaslist = NIL;
        aliaslc = NULL;
        numaliases = 0;
    }
 
    for (varattno = 0; varattno < maxattrs; varattno++)
    {
        Form_pg_attribute attr = TupleDescAttr(tupdesc, varattno);
        String     *attrname;
 
        if (attr->attisdropped)
        {
            /* Always insert an empty string for a dropped column */
            attrname = makeString(pstrdup(""));
            if (aliaslc)
                alias->colnames = lappend(alias->colnames, attrname);
            numdropped++;
        }
        else if (aliaslc)
        {
            /* Use the next user-supplied alias */
            attrname = lfirst_node(String, aliaslc);
            aliaslc = lnext(aliaslist, aliaslc);
            alias->colnames = lappend(alias->colnames, attrname);
        }
        else
        {
            attrname = makeString(pstrdup(NameStr(attr->attname)));
            /* we're done with the alias if any */
        }
 
        eref->colnames = lappend(eref->colnames, attrname);
    }
 
    /* Too many user-supplied aliases? */
    if (aliaslc)
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
                 errmsg("table \"%s\" has %d columns available but %d columns specified",
                        eref->aliasname, maxattrs - numdropped, numaliases)));
}

References Alias::aliasname, Assert(), Alias::colnames, ereport, errcode(), errmsg(), ERROR, lappend(), lfirst_node, list_head(), list_length(), lnext(), makeString(), NameStr, TupleDescData::natts, NIL, pstrdup(), and TupleDescAttr.

Referenced by addRangeTableEntry(), addRangeTableEntryForENR(), addRangeTableEntryForFunction(), and addRangeTableEntryForRelation().

check_lateral_ref_ok()

static void check_lateral_ref_ok ( ParseState *  pstate, ParseNamespaceItem *  nsitem, int  location  )

static

Definition at line 483 of file parse_relation.c.

{
    if (nsitem->p_lateral_only && !nsitem->p_lateral_ok)
    {
        /* SQL:2008 demands this be an error, not an invisible item */
        RangeTblEntry *rte = nsitem->p_rte;
        char       *refname = nsitem->p_names->aliasname;
 
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
                 errmsg("invalid reference to FROM-clause entry for table \"%s\"",
                        refname),
                 (pstate->p_target_nsitem != NULL &&
                  rte == pstate->p_target_nsitem->p_rte) ?
                 errhint("There is an entry for table \"%s\", but it cannot be referenced from this part of the query.",
                         refname) :
                 errdetail("The combining JOIN type must be INNER or LEFT for a LATERAL reference."),
                 parser_errposition(pstate, location)));
    }
}

References Alias::aliasname, ereport, errcode(), errdetail(), errhint(), errmsg(), ERROR, ParseNamespaceItem::p_lateral_ok, ParseNamespaceItem::p_lateral_only, ParseNamespaceItem::p_names, ParseNamespaceItem::p_rte, ParseState::p_target_nsitem, and parser_errposition().

Referenced by colNameToVar(), scanNameSpaceForRefname(), and scanNameSpaceForRelid().

checkNameSpaceConflicts()

void checkNameSpaceConflicts	(	ParseState *	pstate,
		List *	namespace1,
		List *	namespace2
	)

Definition at line 434 of file parse_relation.c.

{
    ListCell   *l1;
 
    foreach(l1, namespace1)
    {
        ParseNamespaceItem *nsitem1 = (ParseNamespaceItem *) lfirst(l1);
        RangeTblEntry *rte1 = nsitem1->p_rte;
        const char *aliasname1 = nsitem1->p_names->aliasname;
        ListCell   *l2;
 
        if (!nsitem1->p_rel_visible)
            continue;
 
        foreach(l2, namespace2)
        {
            ParseNamespaceItem *nsitem2 = (ParseNamespaceItem *) lfirst(l2);
            RangeTblEntry *rte2 = nsitem2->p_rte;
            const char *aliasname2 = nsitem2->p_names->aliasname;
 
            if (!nsitem2->p_rel_visible)
                continue;
            if (strcmp(aliasname2, aliasname1) != 0)
                continue;       /* definitely no conflict */
            if (rte1->rtekind == RTE_RELATION && rte1->alias == NULL &&
                rte2->rtekind == RTE_RELATION && rte2->alias == NULL &&
                rte1->relid != rte2->relid)
                continue;       /* no conflict per SQL rule */
            ereport(ERROR,
                    (errcode(ERRCODE_DUPLICATE_ALIAS),
                     errmsg("table name \"%s\" specified more than once",
                            aliasname1)));
        }
    }
}

References RangeTblEntry::alias, Alias::aliasname, ereport, errcode(), errmsg(), ERROR, lfirst, ParseNamespaceItem::p_names, ParseNamespaceItem::p_rel_visible, ParseNamespaceItem::p_rte, RangeTblEntry::relid, RTE_RELATION, and RangeTblEntry::rtekind.

Referenced by transformFromClause(), and transformFromClauseItem().

chooseScalarFunctionAlias()

static char* chooseScalarFunctionAlias ( Node *  funcexpr, char *  funcname, Alias *  alias, int  nfuncs  )

static

Definition at line 1254 of file parse_relation.c.

{
    char       *pname;
 
    /*
     * If the expression is a simple function call, and the function has a
     * single OUT parameter that is named, use the parameter's name.
     */
    if (funcexpr && IsA(funcexpr, FuncExpr))
    {
        pname = get_func_result_name(((FuncExpr *) funcexpr)->funcid);
        if (pname)
            return pname;
    }
 
    /*
     * If there's just one function in the RTE, and the user gave an RTE alias
     * name, use that name.  (This makes FROM func() AS foo use "foo" as the
     * column name as well as the table alias.)
     */
    if (nfuncs == 1 && alias)
        return alias->aliasname;
 
    /*
     * Otherwise use the function name.
     */
    return funcname;
}

References Alias::aliasname, funcname, get_func_result_name(), and IsA.

Referenced by addRangeTableEntryForFunction().

colNameToVar()

Node* colNameToVar	(	ParseState *	pstate,
		const char *	colname,
		bool	localonly,
		int	location
	)

Definition at line 883 of file parse_relation.c.

{
    Node       *result = NULL;
    int         sublevels_up = 0;
    ParseState *orig_pstate = pstate;
 
    while (pstate != NULL)
    {
        ListCell   *l;
 
        foreach(l, pstate->p_namespace)
        {
            ParseNamespaceItem *nsitem = (ParseNamespaceItem *) lfirst(l);
            Node       *newresult;
 
            /* Ignore table-only items */
            if (!nsitem->p_cols_visible)
                continue;
            /* If not inside LATERAL, ignore lateral-only items */
            if (nsitem->p_lateral_only && !pstate->p_lateral_active)
                continue;
 
            /* use orig_pstate here for consistency with other callers */
            newresult = scanNSItemForColumn(orig_pstate, nsitem, sublevels_up,
                                            colname, location);
 
            if (newresult)
            {
                if (result)
                    ereport(ERROR,
                            (errcode(ERRCODE_AMBIGUOUS_COLUMN),
                             errmsg("column reference \"%s\" is ambiguous",
                                    colname),
                             parser_errposition(pstate, location)));
                check_lateral_ref_ok(pstate, nsitem, location);
                result = newresult;
            }
        }
 
        if (result != NULL || localonly)
            break;              /* found, or don't want to look at parent */
 
        pstate = pstate->parentParseState;
        sublevels_up++;
    }
 
    return result;
}

References check_lateral_ref_ok(), ereport, errcode(), errmsg(), ERROR, lfirst, ParseNamespaceItem::p_cols_visible, ParseState::p_lateral_active, ParseNamespaceItem::p_lateral_only, ParseState::p_namespace, ParseState::parentParseState, parser_errposition(), and scanNSItemForColumn().

Referenced by findTargetlistEntrySQL92(), and transformColumnRef().

errorMissingColumn()

void errorMissingColumn	(	ParseState *	pstate,
		const char *	relname,
		const char *	colname,
		int	location
	)

Definition at line 3662 of file parse_relation.c.

{
    FuzzyAttrMatchState *state;
 
    /*
     * Search the entire rtable looking for possible matches.  If we find one,
     * emit a hint about it.
     */
    state = searchRangeTableForCol(pstate, relname, colname, location);
 
    /*
     * If there are exact match(es), they must be inaccessible for some
     * reason.
     */
    if (state->rexact1)
    {
        /*
         * We don't try too hard when there's multiple inaccessible exact
         * matches, but at least be sure that we don't misleadingly suggest
         * that there's only one.
         */
        if (state->rexact2)
            ereport(ERROR,
                    (errcode(ERRCODE_UNDEFINED_COLUMN),
                     relname ?
                     errmsg("column %s.%s does not exist", relname, colname) :
                     errmsg("column \"%s\" does not exist", colname),
                     errdetail("There are columns named \"%s\", but they are in tables that cannot be referenced from this part of the query.",
                               colname),
                     !relname ? errhint("Try using a table-qualified name.") : 0,
                     parser_errposition(pstate, location)));
        /* Single exact match, so try to determine why it's inaccessible. */
        ereport(ERROR,
                (errcode(ERRCODE_UNDEFINED_COLUMN),
                 relname ?
                 errmsg("column %s.%s does not exist", relname, colname) :
                 errmsg("column \"%s\" does not exist", colname),
                 errdetail("There is a column named \"%s\" in table \"%s\", but it cannot be referenced from this part of the query.",
                           colname, state->rexact1->eref->aliasname),
                 rte_visible_if_lateral(pstate, state->rexact1) ?
                 errhint("To reference that column, you must mark this subquery with LATERAL.") :
                 (!relname && rte_visible_if_qualified(pstate, state->rexact1)) ?
                 errhint("To reference that column, you must use a table-qualified name.") : 0,
                 parser_errposition(pstate, location)));
    }
 
    if (!state->rsecond)
    {
        /* If we found no match at all, we have little to report */
        if (!state->rfirst)
            ereport(ERROR,
                    (errcode(ERRCODE_UNDEFINED_COLUMN),
                     relname ?
                     errmsg("column %s.%s does not exist", relname, colname) :
                     errmsg("column \"%s\" does not exist", colname),
                     parser_errposition(pstate, location)));
        /* Handle case where we have a single alternative spelling to offer */
        ereport(ERROR,
                (errcode(ERRCODE_UNDEFINED_COLUMN),
                 relname ?
                 errmsg("column %s.%s does not exist", relname, colname) :
                 errmsg("column \"%s\" does not exist", colname),
                 errhint("Perhaps you meant to reference the column \"%s.%s\".",
                         state->rfirst->eref->aliasname,
                         strVal(list_nth(state->rfirst->eref->colnames,
                                         state->first - 1))),
                 parser_errposition(pstate, location)));
    }
    else
    {
        /* Handle case where there are two equally useful column hints */
        ereport(ERROR,
                (errcode(ERRCODE_UNDEFINED_COLUMN),
                 relname ?
                 errmsg("column %s.%s does not exist", relname, colname) :
                 errmsg("column \"%s\" does not exist", colname),
                 errhint("Perhaps you meant to reference the column \"%s.%s\" or the column \"%s.%s\".",
                         state->rfirst->eref->aliasname,
                         strVal(list_nth(state->rfirst->eref->colnames,
                                         state->first - 1)),
                         state->rsecond->eref->aliasname,
                         strVal(list_nth(state->rsecond->eref->colnames,
                                         state->second - 1))),
                 parser_errposition(pstate, location)));
    }
}

References ereport, errcode(), errdetail(), errhint(), errmsg(), ERROR, list_nth(), parser_errposition(), relname, rte_visible_if_lateral(), rte_visible_if_qualified(), searchRangeTableForCol(), and strVal.

Referenced by transformColumnRef().

errorMissingRTE()

void errorMissingRTE	(	ParseState *	pstate,
		RangeVar *	relation
	)

Definition at line 3591 of file parse_relation.c.

{
    RangeTblEntry *rte;
    const char *badAlias = NULL;
 
    /*
     * Check to see if there are any potential matches in the query's
     * rangetable.  (Note: cases involving a bad schema name in the RangeVar
     * will throw error immediately here.  That seems OK.)
     */
    rte = searchRangeTableForRel(pstate, relation);
 
    /*
     * If we found a match that has an alias and the alias is visible in the
     * namespace, then the problem is probably use of the relation's real name
     * instead of its alias, ie "SELECT foo.* FROM foo f". This mistake is
     * common enough to justify a specific hint.
     *
     * If we found a match that doesn't meet those criteria, assume the
     * problem is illegal use of a relation outside its scope, as in the
     * MySQL-ism "SELECT ... FROM a, b LEFT JOIN c ON (a.x = c.y)".
     */
    if (rte && rte->alias &&
        strcmp(rte->eref->aliasname, relation->relname) != 0)
    {
        ParseNamespaceItem *nsitem;
        int         sublevels_up;
 
        nsitem = refnameNamespaceItem(pstate, NULL, rte->eref->aliasname,
                                      relation->location,
                                      &sublevels_up);
        if (nsitem && nsitem->p_rte == rte)
            badAlias = rte->eref->aliasname;
    }
 
    /* If it looks like the user forgot to use an alias, hint about that */
    if (badAlias)
        ereport(ERROR,
                (errcode(ERRCODE_UNDEFINED_TABLE),
                 errmsg("invalid reference to FROM-clause entry for table \"%s\"",
                        relation->relname),
                 errhint("Perhaps you meant to reference the table alias \"%s\".",
                         badAlias),
                 parser_errposition(pstate, relation->location)));
    /* Hint about case where we found an (inaccessible) exact match */
    else if (rte)
        ereport(ERROR,
                (errcode(ERRCODE_UNDEFINED_TABLE),
                 errmsg("invalid reference to FROM-clause entry for table \"%s\"",
                        relation->relname),
                 errdetail("There is an entry for table \"%s\", but it cannot be referenced from this part of the query.",
                           rte->eref->aliasname),
                 rte_visible_if_lateral(pstate, rte) ?
                 errhint("To reference that table, you must mark this subquery with LATERAL.") : 0,
                 parser_errposition(pstate, relation->location)));
    /* Else, we have nothing to offer but the bald statement of error */
    else
        ereport(ERROR,
                (errcode(ERRCODE_UNDEFINED_TABLE),
                 errmsg("missing FROM-clause entry for table \"%s\"",
                        relation->relname),
                 parser_errposition(pstate, relation->location)));
}

References RangeTblEntry::alias, Alias::aliasname, RangeTblEntry::eref, ereport, errcode(), ERRCODE_UNDEFINED_TABLE, errdetail(), errhint(), errmsg(), ERROR, RangeVar::location, ParseNamespaceItem::p_rte, parser_errposition(), refnameNamespaceItem(), RangeVar::relname, rte_visible_if_lateral(), and searchRangeTableForRel().

Referenced by ExpandColumnRefStar(), and transformColumnRef().

expandNSItemAttrs()

List* expandNSItemAttrs	(	ParseState *	pstate,
		ParseNamespaceItem *	nsitem,
		int	sublevels_up,
		bool	require_col_privs,
		int	location
	)

Definition at line 3188 of file parse_relation.c.

{
    RangeTblEntry *rte = nsitem->p_rte;
    RTEPermissionInfo *perminfo = nsitem->p_perminfo;
    List       *names,
               *vars;
    ListCell   *name,
               *var;
    List       *te_list = NIL;
 
    vars = expandNSItemVars(pstate, nsitem, sublevels_up, location, &names);
 
    /*
     * Require read access to the table.  This is normally redundant with the
     * markVarForSelectPriv calls below, but not if the table has zero
     * columns.  We need not do anything if the nsitem is for a join: its
     * component tables will have been marked ACL_SELECT when they were added
     * to the rangetable.  (This step changes things only for the target
     * relation of UPDATE/DELETE, which cannot be under a join.)
     */
    if (rte->rtekind == RTE_RELATION)
    {
        Assert(perminfo != NULL);
        perminfo->requiredPerms |= ACL_SELECT;
    }
 
    forboth(name, names, var, vars)
    {
        char       *label = strVal(lfirst(name));
        Var        *varnode = (Var *) lfirst(var);
        TargetEntry *te;
 
        te = makeTargetEntry((Expr *) varnode,
                             (AttrNumber) pstate->p_next_resno++,
                             label,
                             false);
        te_list = lappend(te_list, te);
 
        if (require_col_privs)
        {
            /* Require read access to each column */
            markVarForSelectPriv(pstate, varnode);
        }
    }
 
    Assert(name == NULL && var == NULL);    /* lists not the same length? */
 
    return te_list;
}

References ACL_SELECT, Assert(), expandNSItemVars(), forboth, label, lappend(), lfirst, makeTargetEntry(), markVarForSelectPriv(), name, NIL, ParseState::p_next_resno, ParseNamespaceItem::p_perminfo, ParseNamespaceItem::p_rte, RTEPermissionInfo::requiredPerms, RTE_RELATION, RangeTblEntry::rtekind, and strVal.

Referenced by ExpandAllTables(), ExpandSingleTable(), and transformValuesClause().

expandNSItemVars()

List* expandNSItemVars	(	ParseState *	pstate,
		ParseNamespaceItem *	nsitem,
		int	sublevels_up,
		int	location,
		List **	colnames
	)

Definition at line 3124 of file parse_relation.c.

{
    List       *result = NIL;
    int         colindex;
    ListCell   *lc;
 
    if (colnames)
        *colnames = NIL;
    colindex = 0;
    foreach(lc, nsitem->p_names->colnames)
    {
        String     *colnameval = lfirst(lc);
        const char *colname = strVal(colnameval);
        ParseNamespaceColumn *nscol = nsitem->p_nscolumns + colindex;
 
        if (nscol->p_dontexpand)
        {
            /* skip */
        }
        else if (colname[0])
        {
            Var        *var;
 
            Assert(nscol->p_varno > 0);
            var = makeVar(nscol->p_varno,
                          nscol->p_varattno,
                          nscol->p_vartype,
                          nscol->p_vartypmod,
                          nscol->p_varcollid,
                          sublevels_up);
            /* makeVar doesn't offer parameters for these, so set by hand: */
            var->varnosyn = nscol->p_varnosyn;
            var->varattnosyn = nscol->p_varattnosyn;
            var->location = location;
 
            /* ... and update varnullingrels */
            markNullableIfNeeded(pstate, var);
 
            result = lappend(result, var);
            if (colnames)
                *colnames = lappend(*colnames, colnameval);
        }
        else
        {
            /* dropped column, ignore */
            Assert(nscol->p_varno == 0);
        }
        colindex++;
    }
    return result;
}

References Assert(), Alias::colnames, lappend(), lfirst, Var::location, makeVar(), markNullableIfNeeded(), NIL, ParseNamespaceColumn::p_dontexpand, ParseNamespaceItem::p_names, ParseNamespaceItem::p_nscolumns, ParseNamespaceColumn::p_varattno, ParseNamespaceColumn::p_varattnosyn, ParseNamespaceColumn::p_varcollid, ParseNamespaceColumn::p_varno, ParseNamespaceColumn::p_varnosyn, ParseNamespaceColumn::p_vartype, ParseNamespaceColumn::p_vartypmod, and strVal.

Referenced by coerce_record_to_complex(), expandNSItemAttrs(), and ExpandSingleTable().

expandRelation()

static void expandRelation ( Oid  relid, Alias *  eref, int  rtindex, int  sublevels_up, int  location, bool  include_dropped, List **  colnames, List **  colvars  )

static

Definition at line 3018 of file parse_relation.c.

{
    Relation    rel;
 
    /* Get the tupledesc and turn it over to expandTupleDesc */
    rel = relation_open(relid, AccessShareLock);
    expandTupleDesc(rel->rd_att, eref, rel->rd_att->natts, 0,
                    rtindex, sublevels_up,
                    location, include_dropped,
                    colnames, colvars);
    relation_close(rel, AccessShareLock);
}

References AccessShareLock, expandTupleDesc(), TupleDescData::natts, RelationData::rd_att, relation_close(), and relation_open().

Referenced by expandRTE().

expandRTE()

void expandRTE	(	RangeTblEntry *	rte,
		int	rtindex,
		int	sublevels_up,
		int	location,
		bool	include_dropped,
		List **	colnames,
		List **	colvars
	)

Definition at line 2665 of file parse_relation.c.

{
    int         varattno;
 
    if (colnames)
        *colnames = NIL;
    if (colvars)
        *colvars = NIL;
 
    switch (rte->rtekind)
    {
        case RTE_RELATION:
            /* Ordinary relation RTE */
            expandRelation(rte->relid, rte->eref,
                           rtindex, sublevels_up, location,
                           include_dropped, colnames, colvars);
            break;
        case RTE_SUBQUERY:
            {
                /* Subquery RTE */
                ListCell   *aliasp_item = list_head(rte->eref->colnames);
                ListCell   *tlistitem;
 
                varattno = 0;
                foreach(tlistitem, rte->subquery->targetList)
                {
                    TargetEntry *te = (TargetEntry *) lfirst(tlistitem);
 
                    if (te->resjunk)
                        continue;
                    varattno++;
                    Assert(varattno == te->resno);
 
                    /*
                     * Formerly it was possible for the subquery tlist to have
                     * more non-junk entries than the colnames list does (if
                     * this RTE has been expanded from a view that has more
                     * columns than it did when the current query was parsed).
                     * Now that ApplyRetrieveRule cleans up such cases, we
                     * shouldn't see that anymore, but let's just check.
                     */
                    if (!aliasp_item)
                        elog(ERROR, "too few column names for subquery %s",
                             rte->eref->aliasname);
 
                    if (colnames)
                    {
                        char       *label = strVal(lfirst(aliasp_item));
 
                        *colnames = lappend(*colnames, makeString(pstrdup(label)));
                    }
 
                    if (colvars)
                    {
                        Var        *varnode;
 
                        varnode = makeVar(rtindex, varattno,
                                          exprType((Node *) te->expr),
                                          exprTypmod((Node *) te->expr),
                                          exprCollation((Node *) te->expr),
                                          sublevels_up);
                        varnode->location = location;
 
                        *colvars = lappend(*colvars, varnode);
                    }
 
                    aliasp_item = lnext(rte->eref->colnames, aliasp_item);
                }
            }
            break;
        case RTE_FUNCTION:
            {
                /* Function RTE */
                int         atts_done = 0;
                ListCell   *lc;
 
                foreach(lc, rte->functions)
                {
                    RangeTblFunction *rtfunc = (RangeTblFunction *) lfirst(lc);
                    TypeFuncClass functypclass;
                    Oid         funcrettype;
                    TupleDesc   tupdesc;
 
                    functypclass = get_expr_result_type(rtfunc->funcexpr,
                                                        &funcrettype,
                                                        &tupdesc);
                    if (functypclass == TYPEFUNC_COMPOSITE ||
                        functypclass == TYPEFUNC_COMPOSITE_DOMAIN)
                    {
                        /* Composite data type, e.g. a table's row type */
                        Assert(tupdesc);
                        expandTupleDesc(tupdesc, rte->eref,
                                        rtfunc->funccolcount, atts_done,
                                        rtindex, sublevels_up, location,
                                        include_dropped, colnames, colvars);
                    }
                    else if (functypclass == TYPEFUNC_SCALAR)
                    {
                        /* Base data type, i.e. scalar */
                        if (colnames)
                            *colnames = lappend(*colnames,
                                                list_nth(rte->eref->colnames,
                                                         atts_done));
 
                        if (colvars)
                        {
                            Var        *varnode;
 
                            varnode = makeVar(rtindex, atts_done + 1,
                                              funcrettype,
                                              exprTypmod(rtfunc->funcexpr),
                                              exprCollation(rtfunc->funcexpr),
                                              sublevels_up);
                            varnode->location = location;
 
                            *colvars = lappend(*colvars, varnode);
                        }
                    }
                    else if (functypclass == TYPEFUNC_RECORD)
                    {
                        if (colnames)
                        {
                            List       *namelist;
 
                            /* extract appropriate subset of column list */
                            namelist = list_copy_tail(rte->eref->colnames,
                                                      atts_done);
                            namelist = list_truncate(namelist,
                                                     rtfunc->funccolcount);
                            *colnames = list_concat(*colnames, namelist);
                        }
 
                        if (colvars)
                        {
                            ListCell   *l1;
                            ListCell   *l2;
                            ListCell   *l3;
                            int         attnum = atts_done;
 
                            forthree(l1, rtfunc->funccoltypes,
                                     l2, rtfunc->funccoltypmods,
                                     l3, rtfunc->funccolcollations)
                            {
                                Oid         attrtype = lfirst_oid(l1);
                                int32       attrtypmod = lfirst_int(l2);
                                Oid         attrcollation = lfirst_oid(l3);
                                Var        *varnode;
 
                                attnum++;
                                varnode = makeVar(rtindex,
                                                  attnum,
                                                  attrtype,
                                                  attrtypmod,
                                                  attrcollation,
                                                  sublevels_up);
                                varnode->location = location;
                                *colvars = lappend(*colvars, varnode);
                            }
                        }
                    }
                    else
                    {
                        /* addRangeTableEntryForFunction should've caught this */
                        elog(ERROR, "function in FROM has unsupported return type");
                    }
                    atts_done += rtfunc->funccolcount;
                }
 
                /* Append the ordinality column if any */
                if (rte->funcordinality)
                {
                    if (colnames)
                        *colnames = lappend(*colnames,
                                            llast(rte->eref->colnames));
 
                    if (colvars)
                    {
                        Var        *varnode = makeVar(rtindex,
                                                      atts_done + 1,
                                                      INT8OID,
                                                      -1,
                                                      InvalidOid,
                                                      sublevels_up);
 
                        *colvars = lappend(*colvars, varnode);
                    }
                }
            }
            break;
        case RTE_JOIN:
            {
                /* Join RTE */
                ListCell   *colname;
                ListCell   *aliasvar;
 
                Assert(list_length(rte->eref->colnames) == list_length(rte->joinaliasvars));
 
                varattno = 0;
                forboth(colname, rte->eref->colnames, aliasvar, rte->joinaliasvars)
                {
                    Node       *avar = (Node *) lfirst(aliasvar);
 
                    varattno++;
 
                    /*
                     * During ordinary parsing, there will never be any
                     * deleted columns in the join.  While this function is
                     * also used by the rewriter and planner, they do not
                     * currently call it on any JOIN RTEs.  Therefore, this
                     * next bit is dead code, but it seems prudent to handle
                     * the case correctly anyway.
                     */
                    if (avar == NULL)
                    {
                        if (include_dropped)
                        {
                            if (colnames)
                                *colnames = lappend(*colnames,
                                                    makeString(pstrdup("")));
                            if (colvars)
                            {
                                /*
                                 * Can't use join's column type here (it might
                                 * be dropped!); but it doesn't really matter
                                 * what type the Const claims to be.
                                 */
                                *colvars = lappend(*colvars,
                                                   makeNullConst(INT4OID, -1,
                                                                 InvalidOid));
                            }
                        }
                        continue;
                    }
 
                    if (colnames)
                    {
                        char       *label = strVal(lfirst(colname));
 
                        *colnames = lappend(*colnames,
                                            makeString(pstrdup(label)));
                    }
 
                    if (colvars)
                    {
                        Var        *varnode;
 
                        /*
                         * If the joinaliasvars entry is a simple Var, just
                         * copy it (with adjustment of varlevelsup and
                         * location); otherwise it is a JOIN USING column and
                         * we must generate a join alias Var.  This matches
                         * the results that expansion of "join.*" by
                         * expandNSItemVars would have produced, if we had
                         * access to the ParseNamespaceItem for the join.
                         */
                        if (IsA(avar, Var))
                        {
                            varnode = copyObject((Var *) avar);
                            varnode->varlevelsup = sublevels_up;
                        }
                        else
                            varnode = makeVar(rtindex, varattno,
                                              exprType(avar),
                                              exprTypmod(avar),
                                              exprCollation(avar),
                                              sublevels_up);
                        varnode->location = location;
 
                        *colvars = lappend(*colvars, varnode);
                    }
                }
            }
            break;
        case RTE_TABLEFUNC:
        case RTE_VALUES:
        case RTE_CTE:
        case RTE_NAMEDTUPLESTORE:
            {
                /* Tablefunc, Values, CTE, or ENR RTE */
                ListCell   *aliasp_item = list_head(rte->eref->colnames);
                ListCell   *lct;
                ListCell   *lcm;
                ListCell   *lcc;
 
                varattno = 0;
                forthree(lct, rte->coltypes,
                         lcm, rte->coltypmods,
                         lcc, rte->colcollations)
                {
                    Oid         coltype = lfirst_oid(lct);
                    int32       coltypmod = lfirst_int(lcm);
                    Oid         colcoll = lfirst_oid(lcc);
 
                    varattno++;
 
                    if (colnames)
                    {
                        /* Assume there is one alias per output column */
                        if (OidIsValid(coltype))
                        {
                            char       *label = strVal(lfirst(aliasp_item));
 
                            *colnames = lappend(*colnames,
                                                makeString(pstrdup(label)));
                        }
                        else if (include_dropped)
                            *colnames = lappend(*colnames,
                                                makeString(pstrdup("")));
 
                        aliasp_item = lnext(rte->eref->colnames, aliasp_item);
                    }
 
                    if (colvars)
                    {
                        if (OidIsValid(coltype))
                        {
                            Var        *varnode;
 
                            varnode = makeVar(rtindex, varattno,
                                              coltype, coltypmod, colcoll,
                                              sublevels_up);
                            varnode->location = location;
 
                            *colvars = lappend(*colvars, varnode);
                        }
                        else if (include_dropped)
                        {
                            /*
                             * It doesn't really matter what type the Const
                             * claims to be.
                             */
                            *colvars = lappend(*colvars,
                                               makeNullConst(INT4OID, -1,
                                                             InvalidOid));
                        }
                    }
                }
            }
            break;
        case RTE_RESULT:
            /* These expose no columns, so nothing to do */
            break;
        default:
            elog(ERROR, "unrecognized RTE kind: %d", (int) rte->rtekind);
    }
}

References Alias::aliasname, Assert(), attnum, RangeTblEntry::colcollations, Alias::colnames, RangeTblEntry::coltypes, RangeTblEntry::coltypmods, copyObject, elog(), RangeTblEntry::eref, ERROR, expandRelation(), expandTupleDesc(), TargetEntry::expr, exprCollation(), exprType(), exprTypmod(), forboth, forthree, RangeTblFunction::funcexpr, RangeTblEntry::funcordinality, RangeTblEntry::functions, get_expr_result_type(), InvalidOid, IsA, RangeTblEntry::joinaliasvars, label, lappend(), lfirst, lfirst_int, lfirst_oid, list_concat(), list_copy_tail(), list_head(), list_length(), list_nth(), list_truncate(), llast, lnext(), Var::location, makeNullConst(), makeString(), makeVar(), NIL, OidIsValid, pstrdup(), RangeTblEntry::relid, TargetEntry::resno, RTE_CTE, RTE_FUNCTION, RTE_JOIN, RTE_NAMEDTUPLESTORE, RTE_RELATION, RTE_RESULT, RTE_SUBQUERY, RTE_TABLEFUNC, RTE_VALUES, RangeTblEntry::rtekind, strVal, RangeTblEntry::subquery, Query::targetList, TYPEFUNC_COMPOSITE, TYPEFUNC_COMPOSITE_DOMAIN, TYPEFUNC_RECORD, TYPEFUNC_SCALAR, and Var::varlevelsup.

Referenced by build_physical_tlist(), expandRecordVariable(), pullup_replace_vars_callback(), ReplaceVarsFromTargetList_callback(), set_relation_column_names(), and transformWholeRowRef().

expandTupleDesc()

static void expandTupleDesc ( TupleDesc  tupdesc, Alias *  eref, int  count, int  offset, int  rtindex, int  sublevels_up, int  location, bool  include_dropped, List **  colnames, List **  colvars  )

static

Definition at line 3043 of file parse_relation.c.

{
    ListCell   *aliascell;
    int         varattno;
 
    aliascell = (offset < list_length(eref->colnames)) ?
        list_nth_cell(eref->colnames, offset) : NULL;
 
    Assert(count <= tupdesc->natts);
    for (varattno = 0; varattno < count; varattno++)
    {
        Form_pg_attribute attr = TupleDescAttr(tupdesc, varattno);
 
        if (attr->attisdropped)
        {
            if (include_dropped)
            {
                if (colnames)
                    *colnames = lappend(*colnames, makeString(pstrdup("")));
                if (colvars)
                {
                    /*
                     * can't use atttypid here, but it doesn't really matter
                     * what type the Const claims to be.
                     */
                    *colvars = lappend(*colvars,
                                       makeNullConst(INT4OID, -1, InvalidOid));
                }
            }
            if (aliascell)
                aliascell = lnext(eref->colnames, aliascell);
            continue;
        }
 
        if (colnames)
        {
            char       *label;
 
            if (aliascell)
            {
                label = strVal(lfirst(aliascell));
                aliascell = lnext(eref->colnames, aliascell);
            }
            else
            {
                /* If we run out of aliases, use the underlying name */
                label = NameStr(attr->attname);
            }
            *colnames = lappend(*colnames, makeString(pstrdup(label)));
        }
 
        if (colvars)
        {
            Var        *varnode;
 
            varnode = makeVar(rtindex, varattno + offset + 1,
                              attr->atttypid, attr->atttypmod,
                              attr->attcollation,
                              sublevels_up);
            varnode->location = location;
 
            *colvars = lappend(*colvars, varnode);
        }
    }
}

References Assert(), Alias::colnames, InvalidOid, label, lappend(), lfirst, list_length(), list_nth_cell(), lnext(), Var::location, makeNullConst(), makeString(), makeVar(), NameStr, pstrdup(), strVal, and TupleDescAttr.

Referenced by expandRelation(), and expandRTE().

findNSItemForRTE()

static ParseNamespaceItem* findNSItemForRTE ( ParseState *  pstate, RangeTblEntry *  rte  )

static

Definition at line 3755 of file parse_relation.c.

{
    while (pstate != NULL)
    {
        ListCell   *l;
 
        foreach(l, pstate->p_namespace)
        {
            ParseNamespaceItem *nsitem = (ParseNamespaceItem *) lfirst(l);
 
            if (nsitem->p_rte == rte)
                return nsitem;
        }
        pstate = pstate->parentParseState;
    }
    return NULL;
}

References lfirst, ParseState::p_namespace, ParseNamespaceItem::p_rte, and ParseState::parentParseState.

Referenced by rte_visible_if_lateral(), and rte_visible_if_qualified().

get_parse_rowmark()

RowMarkClause* get_parse_rowmark	(	Query *	qry,
		Index	rtindex
	)

Definition at line 3456 of file parse_relation.c.

{
    ListCell   *l;
 
    foreach(l, qry->rowMarks)
    {
        RowMarkClause *rc = (RowMarkClause *) lfirst(l);
 
        if (rc->rti == rtindex)
            return rc;
    }
    return NULL;
}

References lfirst, Query::rowMarks, and RowMarkClause::rti.

Referenced by AcquireRewriteLocks(), applyLockingClause(), and ApplyRetrieveRule().

get_rte_attribute_is_dropped()

bool get_rte_attribute_is_dropped	(	RangeTblEntry *	rte,
		AttrNumber	attnum
	)

Definition at line 3292 of file parse_relation.c.

{
    bool        result;
 
    switch (rte->rtekind)
    {
        case RTE_RELATION:
            {
                /*
                 * Plain relation RTE --- get the attribute's catalog entry
                 */
                HeapTuple   tp;
                Form_pg_attribute att_tup;
 
                tp = SearchSysCache2(ATTNUM,
                                     ObjectIdGetDatum(rte->relid),
                                     Int16GetDatum(attnum));
                if (!HeapTupleIsValid(tp))  /* shouldn't happen */
                    elog(ERROR, "cache lookup failed for attribute %d of relation %u",
                         attnum, rte->relid);
                att_tup = (Form_pg_attribute) GETSTRUCT(tp);
                result = att_tup->attisdropped;
                ReleaseSysCache(tp);
            }
            break;
        case RTE_SUBQUERY:
        case RTE_TABLEFUNC:
        case RTE_VALUES:
        case RTE_CTE:
 
            /*
             * Subselect, Table Functions, Values, CTE RTEs never have dropped
             * columns
             */
            result = false;
            break;
        case RTE_NAMEDTUPLESTORE:
            {
                /* Check dropped-ness by testing for valid coltype */
                if (attnum <= 0 ||
                    attnum > list_length(rte->coltypes))
                    elog(ERROR, "invalid varattno %d", attnum);
                result = !OidIsValid((list_nth_oid(rte->coltypes, attnum - 1)));
            }
            break;
        case RTE_JOIN:
            {
                /*
                 * A join RTE would not have dropped columns when constructed,
                 * but one in a stored rule might contain columns that were
                 * dropped from the underlying tables, if said columns are
                 * nowhere explicitly referenced in the rule.  This will be
                 * signaled to us by a null pointer in the joinaliasvars list.
                 */
                Var        *aliasvar;
 
                if (attnum <= 0 ||
                    attnum > list_length(rte->joinaliasvars))
                    elog(ERROR, "invalid varattno %d", attnum);
                aliasvar = (Var *) list_nth(rte->joinaliasvars, attnum - 1);
 
                result = (aliasvar == NULL);
            }
            break;
        case RTE_FUNCTION:
            {
                /* Function RTE */
                ListCell   *lc;
                int         atts_done = 0;
 
                /*
                 * Dropped attributes are only possible with functions that
                 * return named composite types.  In such a case we have to
                 * look up the result type to see if it currently has this
                 * column dropped.  So first, loop over the funcs until we
                 * find the one that covers the requested column.
                 */
                foreach(lc, rte->functions)
                {
                    RangeTblFunction *rtfunc = (RangeTblFunction *) lfirst(lc);
 
                    if (attnum > atts_done &&
                        attnum <= atts_done + rtfunc->funccolcount)
                    {
                        TupleDesc   tupdesc;
 
                        tupdesc = get_expr_result_tupdesc(rtfunc->funcexpr,
                                                          true);
                        if (tupdesc)
                        {
                            /* Composite data type, e.g. a table's row type */
                            Form_pg_attribute att_tup;
 
                            Assert(tupdesc);
                            Assert(attnum - atts_done <= tupdesc->natts);
                            att_tup = TupleDescAttr(tupdesc,
                                                    attnum - atts_done - 1);
                            return att_tup->attisdropped;
                        }
                        /* Otherwise, it can't have any dropped columns */
                        return false;
                    }
                    atts_done += rtfunc->funccolcount;
                }
 
                /* If we get here, must be looking for the ordinality column */
                if (rte->funcordinality && attnum == atts_done + 1)
                    return false;
 
                /* this probably can't happen ... */
                ereport(ERROR,
                        (errcode(ERRCODE_UNDEFINED_COLUMN),
                         errmsg("column %d of relation \"%s\" does not exist",
                                attnum,
                                rte->eref->aliasname)));
                result = false; /* keep compiler quiet */
            }
            break;
        case RTE_RESULT:
            /* this probably can't happen ... */
            ereport(ERROR,
                    (errcode(ERRCODE_UNDEFINED_COLUMN),
                     errmsg("column %d of relation \"%s\" does not exist",
                            attnum,
                            rte->eref->aliasname)));
            result = false;     /* keep compiler quiet */
            break;
        default:
            elog(ERROR, "unrecognized RTE kind: %d", (int) rte->rtekind);
            result = false;     /* keep compiler quiet */
    }
 
    return result;
}

References Alias::aliasname, Assert(), attnum, ATTNUM, RangeTblEntry::coltypes, elog(), RangeTblEntry::eref, ereport, errcode(), errmsg(), ERROR, RangeTblFunction::funcexpr, RangeTblEntry::funcordinality, RangeTblEntry::functions, get_expr_result_tupdesc(), GETSTRUCT, HeapTupleIsValid, Int16GetDatum(), RangeTblEntry::joinaliasvars, lfirst, list_length(), list_nth(), list_nth_oid(), ObjectIdGetDatum(), OidIsValid, ReleaseSysCache(), RangeTblEntry::relid, RTE_CTE, RTE_FUNCTION, RTE_JOIN, RTE_NAMEDTUPLESTORE, RTE_RELATION, RTE_RESULT, RTE_SUBQUERY, RTE_TABLEFUNC, RTE_VALUES, RangeTblEntry::rtekind, SearchSysCache2(), and TupleDescAttr.

Referenced by AcquireRewriteLocks().

get_rte_attribute_name()

char* get_rte_attribute_name	(	RangeTblEntry *	rte,
		AttrNumber	attnum
	)

Definition at line 3254 of file parse_relation.c.

{
    if (attnum == InvalidAttrNumber)
        return "*";
 
    /*
     * If there is a user-written column alias, use it.
     */
    if (rte->alias &&
        attnum > 0 && attnum <= list_length(rte->alias->colnames))
        return strVal(list_nth(rte->alias->colnames, attnum - 1));
 
    /*
     * If the RTE is a relation, go to the system catalogs not the
     * eref->colnames list.  This is a little slower but it will give the
     * right answer if the column has been renamed since the eref list was
     * built (which can easily happen for rules).
     */
    if (rte->rtekind == RTE_RELATION)
        return get_attname(rte->relid, attnum, false);
 
    /*
     * Otherwise use the column name from eref.  There should always be one.
     */
    if (attnum > 0 && attnum <= list_length(rte->eref->colnames))
        return strVal(list_nth(rte->eref->colnames, attnum - 1));
 
    /* else caller gave us a bogus attnum */
    elog(ERROR, "invalid attnum %d for rangetable entry %s",
         attnum, rte->eref->aliasname);
    return NULL;                /* keep compiler quiet */
}

References RangeTblEntry::alias, Alias::aliasname, attnum, Alias::colnames, elog(), RangeTblEntry::eref, ERROR, get_attname(), InvalidAttrNumber, list_length(), list_nth(), RangeTblEntry::relid, RTE_RELATION, RangeTblEntry::rtekind, and strVal.

Referenced by check_ungrouped_columns_walker(), get_name_for_var_field(), get_variable(), and print_expr().

get_tle_by_resno()

TargetEntry* get_tle_by_resno	(	List *	tlist,
		AttrNumber	resno
	)

Definition at line 3436 of file parse_relation.c.

{
    ListCell   *l;
 
    foreach(l, tlist)
    {
        TargetEntry *tle = (TargetEntry *) lfirst(l);
 
        if (tle->resno == resno)
            return tle;
    }
    return NULL;
}

References lfirst, and TargetEntry::resno.

Referenced by adjust_view_column_set(), count_rowexpr_columns(), create_unique_plan(), currtid_for_view(), examine_simple_variable(), expandRecordVariable(), get_name_for_var_field(), get_variable(), make_sort_from_groupcols(), markTargetListOrigin(), prepare_sort_from_pathkeys(), pullup_replace_vars_callback(), ReplaceVarsFromTargetList_callback(), resolve_special_varno(), rewriteTargetView(), show_grouping_set_keys(), and show_sort_group_keys().

GetCTEForRTE()

CommonTableExpr* GetCTEForRTE	(	ParseState *	pstate,
		RangeTblEntry *	rte,
		int	rtelevelsup
	)

Definition at line 557 of file parse_relation.c.

{
    Index       levelsup;
    ListCell   *lc;
 
    Assert(rte->rtekind == RTE_CTE);
    levelsup = rte->ctelevelsup + rtelevelsup;
    while (levelsup-- > 0)
    {
        pstate = pstate->parentParseState;
        if (!pstate)            /* shouldn't happen */
            elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
    }
    foreach(lc, pstate->p_ctenamespace)
    {
        CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
 
        if (strcmp(cte->ctename, rte->ctename) == 0)
            return cte;
    }
    /* shouldn't happen */
    elog(ERROR, "could not find CTE \"%s\"", rte->ctename);
    return NULL;                /* keep compiler quiet */
}

References Assert(), RangeTblEntry::ctelevelsup, RangeTblEntry::ctename, CommonTableExpr::ctename, elog(), ERROR, lfirst, ParseState::p_ctenamespace, ParseState::parentParseState, RTE_CTE, and RangeTblEntry::rtekind.

Referenced by expandRecordVariable(), and markTargetListOrigin().

GetNSItemByRangeTablePosn()

ParseNamespaceItem* GetNSItemByRangeTablePosn	(	ParseState *	pstate,
		int	varno,
		int	sublevels_up
	)

Definition at line 510 of file parse_relation.c.

{
    ListCell   *lc;
 
    while (sublevels_up-- > 0)
    {
        pstate = pstate->parentParseState;
        Assert(pstate != NULL);
    }
    foreach(lc, pstate->p_namespace)
    {
        ParseNamespaceItem *nsitem = (ParseNamespaceItem *) lfirst(lc);
 
        if (nsitem->p_rtindex == varno)
            return nsitem;
    }
    elog(ERROR, "nsitem not found (internal error)");
    return NULL;                /* keep compiler quiet */
}

References Assert(), elog(), ERROR, lfirst, ParseState::p_namespace, ParseNamespaceItem::p_rtindex, and ParseState::parentParseState.

Referenced by coerce_record_to_complex(), ExpandRowReference(), ParseComplexProjection(), and transformMergeStmt().

GetRTEByRangeTablePosn()

RangeTblEntry* GetRTEByRangeTablePosn	(	ParseState *	pstate,
		int	varno,
		int	sublevels_up
	)

Definition at line 537 of file parse_relation.c.

{
    while (sublevels_up-- > 0)
    {
        pstate = pstate->parentParseState;
        Assert(pstate != NULL);
    }
    Assert(varno > 0 && varno <= list_length(pstate->p_rtable));
    return rt_fetch(varno, pstate->p_rtable);
}

References Assert(), list_length(), ParseState::p_rtable, ParseState::parentParseState, and rt_fetch.

Referenced by count_rowexpr_columns(), expandRecordVariable(), markTargetListOrigin(), and unknown_attribute().

getRTEPermissionInfo()

RTEPermissionInfo* getRTEPermissionInfo	(	List *	rteperminfos,
		RangeTblEntry *	rte
	)

Definition at line 3900 of file parse_relation.c.

{
    RTEPermissionInfo *perminfo;
 
    if (rte->perminfoindex == 0 ||
        rte->perminfoindex > list_length(rteperminfos))
        elog(ERROR, "invalid perminfoindex %u in RTE with relid %u",
             rte->perminfoindex, rte->relid);
    perminfo = list_nth_node(RTEPermissionInfo, rteperminfos,
                             rte->perminfoindex - 1);
    if (perminfo->relid != rte->relid)
        elog(ERROR, "permission info at index %u (with relid=%u) does not match provided RTE (with relid=%u)",
             rte->perminfoindex, perminfo->relid, rte->relid);
 
    return perminfo;
}

References elog(), ERROR, list_length(), list_nth_node, RangeTblEntry::perminfoindex, RangeTblEntry::relid, and RTEPermissionInfo::relid.

Referenced by add_rte_to_flat_rtable(), build_simple_rel(), ExecCheckPermissions(), expand_inherited_rtentry(), get_rel_all_updated_cols(), get_row_security_policies(), GetResultRTEPermissionInfo(), markQueryForLocking(), markRTEForSelectPriv(), rewriteTargetView(), and transformLockingClause().

isFutureCTE()

static bool isFutureCTE ( ParseState *  pstate, const char *  refname  )

static

Definition at line 313 of file parse_relation.c.

{
    for (; pstate != NULL; pstate = pstate->parentParseState)
    {
        ListCell   *lc;
 
        foreach(lc, pstate->p_future_ctes)
        {
            CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
 
            if (strcmp(cte->ctename, refname) == 0)
                return true;
        }
    }
    return false;
}

References CommonTableExpr::ctename, lfirst, ParseState::p_future_ctes, and ParseState::parentParseState.

Referenced by parserOpenTable().

isLockedRefname()

bool isLockedRefname	(	ParseState *	pstate,
		const char *	refname
	)

Definition at line 2581 of file parse_relation.c.

{
    ListCell   *l;
 
    /*
     * If we are in a subquery specified as locked FOR UPDATE/SHARE from
     * parent level, then act as though there's a generic FOR UPDATE here.
     */
    if (pstate->p_locked_from_parent)
        return true;
 
    foreach(l, pstate->p_locking_clause)
    {
        LockingClause *lc = (LockingClause *) lfirst(l);
 
        if (lc->lockedRels == NIL)
        {
            /* all tables used in query */
            return true;
        }
        else if (refname != NULL)
        {
            /* just the named tables */
            ListCell   *l2;
 
            foreach(l2, lc->lockedRels)
            {
                RangeVar   *thisrel = (RangeVar *) lfirst(l2);
 
                if (strcmp(refname, thisrel->relname) == 0)
                    return true;
            }
        }
    }
    return false;
}

References lfirst, LockingClause::lockedRels, NIL, ParseState::p_locked_from_parent, ParseState::p_locking_clause, and RangeVar::relname.

Referenced by addRangeTableEntry(), and transformRangeSubselect().

isQueryUsingTempRelation()

bool isQueryUsingTempRelation

(

Query *

query

)

Definition at line 3821 of file parse_relation.c.

{
    return isQueryUsingTempRelation_walker((Node *) query, NULL);
}

References isQueryUsingTempRelation_walker().

Referenced by DefineView(), and transformCreateTableAsStmt().

isQueryUsingTempRelation_walker()

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

static

Definition at line 3827 of file parse_relation.c.

{
    if (node == NULL)
        return false;
 
    if (IsA(node, Query))
    {
        Query      *query = (Query *) node;
        ListCell   *rtable;
 
        foreach(rtable, query->rtable)
        {
            RangeTblEntry *rte = lfirst(rtable);
 
            if (rte->rtekind == RTE_RELATION)
            {
                Relation    rel = table_open(rte->relid, AccessShareLock);
                char        relpersistence = rel->rd_rel->relpersistence;
 
                table_close(rel, AccessShareLock);
                if (relpersistence == RELPERSISTENCE_TEMP)
                    return true;
            }
        }
 
        return query_tree_walker(query,
                                 isQueryUsingTempRelation_walker,
                                 context,
                                 QTW_IGNORE_JOINALIASES);
    }
 
    return expression_tree_walker(node,
                                  isQueryUsingTempRelation_walker,
                                  context);
}

References AccessShareLock, expression_tree_walker, IsA, lfirst, QTW_IGNORE_JOINALIASES, query_tree_walker, RelationData::rd_rel, RangeTblEntry::relid, Query::rtable, RTE_RELATION, RangeTblEntry::rtekind, table_close(), and table_open().

Referenced by isQueryUsingTempRelation().

markNullableIfNeeded()

void markNullableIfNeeded	(	ParseState *	pstate,
		Var *	var
	)

Definition at line 1035 of file parse_relation.c.

{
    int         rtindex = var->varno;
    Bitmapset  *relids;
 
    /* Find the appropriate pstate */
    for (int lv = 0; lv < var->varlevelsup; lv++)
        pstate = pstate->parentParseState;
 
    /* Find currently-relevant join relids for the Var's rel */
    if (rtindex > 0 && rtindex <= list_length(pstate->p_nullingrels))
        relids = (Bitmapset *) list_nth(pstate->p_nullingrels, rtindex - 1);
    else
        relids = NULL;
 
    /*
     * Merge with any already-declared nulling rels.  (Typically there won't
     * be any, but let's get it right if there are.)
     */
    if (relids != NULL)
        var->varnullingrels = bms_union(var->varnullingrels, relids);
}

References bms_union(), if(), list_length(), list_nth(), ParseState::p_nullingrels, ParseState::parentParseState, Var::varlevelsup, and Var::varno.

Referenced by buildVarFromNSColumn(), expandNSItemVars(), scanNSItemForColumn(), and transformWholeRowRef().

markRTEForSelectPriv()

static void markRTEForSelectPriv ( ParseState *  pstate, int  rtindex, AttrNumber  col  )

static

Definition at line 1066 of file parse_relation.c.

{
    RangeTblEntry *rte = rt_fetch(rtindex, pstate->p_rtable);
 
    if (rte->rtekind == RTE_RELATION)
    {
        RTEPermissionInfo *perminfo;
 
        /* Make sure the rel as a whole is marked for SELECT access */
        perminfo = getRTEPermissionInfo(pstate->p_rteperminfos, rte);
        perminfo->requiredPerms |= ACL_SELECT;
        /* Must offset the attnum to fit in a bitmapset */
        perminfo->selectedCols =
            bms_add_member(perminfo->selectedCols,
                           col - FirstLowInvalidHeapAttributeNumber);
    }
    else if (rte->rtekind == RTE_JOIN)
    {
        if (col == InvalidAttrNumber)
        {
            /*
             * A whole-row reference to a join has to be treated as whole-row
             * references to the two inputs.
             */
            JoinExpr   *j;
 
            if (rtindex > 0 && rtindex <= list_length(pstate->p_joinexprs))
                j = list_nth_node(JoinExpr, pstate->p_joinexprs, rtindex - 1);
            else
                j = NULL;
            if (j == NULL)
                elog(ERROR, "could not find JoinExpr for whole-row reference");
 
            /* Note: we can't see FromExpr here */
            if (IsA(j->larg, RangeTblRef))
            {
                int         varno = ((RangeTblRef *) j->larg)->rtindex;
 
                markRTEForSelectPriv(pstate, varno, InvalidAttrNumber);
            }
            else if (IsA(j->larg, JoinExpr))
            {
                int         varno = ((JoinExpr *) j->larg)->rtindex;
 
                markRTEForSelectPriv(pstate, varno, InvalidAttrNumber);
            }
            else
                elog(ERROR, "unrecognized node type: %d",
                     (int) nodeTag(j->larg));
            if (IsA(j->rarg, RangeTblRef))
            {
                int         varno = ((RangeTblRef *) j->rarg)->rtindex;
 
                markRTEForSelectPriv(pstate, varno, InvalidAttrNumber);
            }
            else if (IsA(j->rarg, JoinExpr))
            {
                int         varno = ((JoinExpr *) j->rarg)->rtindex;
 
                markRTEForSelectPriv(pstate, varno, InvalidAttrNumber);
            }
            else
                elog(ERROR, "unrecognized node type: %d",
                     (int) nodeTag(j->rarg));
        }
        else
        {
            /*
             * Join alias Vars for ordinary columns must refer to merged JOIN
             * USING columns.  We don't need to do anything here, because the
             * join input columns will also be referenced in the join's qual
             * clause, and will get marked for select privilege there.
             */
        }
    }
    /* other RTE types don't require privilege marking */
}

References ACL_SELECT, bms_add_member(), elog(), ERROR, FirstLowInvalidHeapAttributeNumber, getRTEPermissionInfo(), InvalidAttrNumber, IsA, j, list_length(), list_nth_node, nodeTag, ParseState::p_joinexprs, ParseState::p_rtable, ParseState::p_rteperminfos, RTEPermissionInfo::requiredPerms, rt_fetch, RTE_JOIN, RTE_RELATION, RangeTblEntry::rtekind, and RTEPermissionInfo::selectedCols.

Referenced by markVarForSelectPriv().

markVarForSelectPriv()

void markVarForSelectPriv	(	ParseState *	pstate,
		Var *	var
	)

Definition at line 1150 of file parse_relation.c.

{
    Index       lv;
 
    Assert(IsA(var, Var));
    /* Find the appropriate pstate if it's an uplevel Var */
    for (lv = 0; lv < var->varlevelsup; lv++)
        pstate = pstate->parentParseState;
    markRTEForSelectPriv(pstate, var->varno, var->varattno);
}

References Assert(), IsA, markRTEForSelectPriv(), ParseState::parentParseState, Var::varattno, Var::varlevelsup, and Var::varno.

Referenced by expandNSItemAttrs(), ExpandSingleTable(), scanNSItemForColumn(), transformJoinUsingClause(), and transformWholeRowRef().

parserOpenTable()

Relation parserOpenTable	(	ParseState *	pstate,
		const RangeVar *	relation,
		int	lockmode
	)

Definition at line 1418 of file parse_relation.c.

{
    Relation    rel;
    ParseCallbackState pcbstate;
 
    setup_parser_errposition_callback(&pcbstate, pstate, relation->location);
    rel = table_openrv_extended(relation, lockmode, true);
    if (rel == NULL)
    {
        if (relation->schemaname)
            ereport(ERROR,
                    (errcode(ERRCODE_UNDEFINED_TABLE),
                     errmsg("relation \"%s.%s\" does not exist",
                            relation->schemaname, relation->relname)));
        else
        {
            /*
             * An unqualified name might have been meant as a reference to
             * some not-yet-in-scope CTE.  The bare "does not exist" message
             * has proven remarkably unhelpful for figuring out such problems,
             * so we take pains to offer a specific hint.
             */
            if (isFutureCTE(pstate, relation->relname))
                ereport(ERROR,
                        (errcode(ERRCODE_UNDEFINED_TABLE),
                         errmsg("relation \"%s\" does not exist",
                                relation->relname),
                         errdetail("There is a WITH item named \"%s\", but it cannot be referenced from this part of the query.",
                                   relation->relname),
                         errhint("Use WITH RECURSIVE, or re-order the WITH items to remove forward references.")));
            else
                ereport(ERROR,
                        (errcode(ERRCODE_UNDEFINED_TABLE),
                         errmsg("relation \"%s\" does not exist",
                                relation->relname)));
        }
    }
    cancel_parser_errposition_callback(&pcbstate);
    return rel;
}

References cancel_parser_errposition_callback(), ereport, errcode(), ERRCODE_UNDEFINED_TABLE, errdetail(), errhint(), errmsg(), ERROR, isFutureCTE(), RangeVar::location, RangeVar::relname, RangeVar::schemaname, setup_parser_errposition_callback(), and table_openrv_extended().

Referenced by addRangeTableEntry(), and setTargetTable().

refnameNamespaceItem()

ParseNamespaceItem* refnameNamespaceItem	(	ParseState *	pstate,
		const char *	schemaname,
		const char *	refname,
		int	location,
		int *	sublevels_up
	)

Definition at line 129 of file parse_relation.c.

{
    Oid         relId = InvalidOid;
 
    if (sublevels_up)
        *sublevels_up = 0;
 
    if (schemaname != NULL)
    {
        Oid         namespaceId;
 
        /*
         * We can use LookupNamespaceNoError() here because we are only
         * interested in finding existing RTEs.  Checking USAGE permission on
         * the schema is unnecessary since it would have already been checked
         * when the RTE was made.  Furthermore, we want to report "RTE not
         * found", not "no permissions for schema", if the name happens to
         * match a schema name the user hasn't got access to.
         */
        namespaceId = LookupNamespaceNoError(schemaname);
        if (!OidIsValid(namespaceId))
            return NULL;
        relId = get_relname_relid(refname, namespaceId);
        if (!OidIsValid(relId))
            return NULL;
    }
 
    while (pstate != NULL)
    {
        ParseNamespaceItem *result;
 
        if (OidIsValid(relId))
            result = scanNameSpaceForRelid(pstate, relId, location);
        else
            result = scanNameSpaceForRefname(pstate, refname, location);
 
        if (result)
            return result;
 
        if (sublevels_up)
            (*sublevels_up)++;
        else
            break;
 
        pstate = pstate->parentParseState;
    }
    return NULL;
}

References get_relname_relid(), InvalidOid, LookupNamespaceNoError(), OidIsValid, ParseState::parentParseState, scanNameSpaceForRefname(), and scanNameSpaceForRelid().

Referenced by errorMissingRTE(), ExpandColumnRefStar(), and transformColumnRef().

rte_visible_if_lateral()

static bool rte_visible_if_lateral ( ParseState *  pstate, RangeTblEntry *  rte  )

static

Definition at line 3783 of file parse_relation.c.

{
    ParseNamespaceItem *nsitem;
 
    /* If LATERAL *is* active, we're clearly barking up the wrong tree */
    if (pstate->p_lateral_active)
        return false;
    nsitem = findNSItemForRTE(pstate, rte);
    if (nsitem)
    {
        /* Found it, report whether it's LATERAL-only */
        return nsitem->p_lateral_only && nsitem->p_lateral_ok;
    }
    return false;
}

References findNSItemForRTE(), ParseState::p_lateral_active, ParseNamespaceItem::p_lateral_ok, and ParseNamespaceItem::p_lateral_only.

Referenced by errorMissingColumn(), and errorMissingRTE().

rte_visible_if_qualified()

static bool rte_visible_if_qualified ( ParseState *  pstate, RangeTblEntry *  rte  )

static

Definition at line 3803 of file parse_relation.c.

{
    ParseNamespaceItem *nsitem = findNSItemForRTE(pstate, rte);
 
    if (nsitem)
    {
        /* Found it, report whether it's relation-only */
        return nsitem->p_rel_visible && !nsitem->p_cols_visible;
    }
    return false;
}

References findNSItemForRTE(), ParseNamespaceItem::p_cols_visible, and ParseNamespaceItem::p_rel_visible.

Referenced by errorMissingColumn().

scanNameSpaceForCTE()

CommonTableExpr* scanNameSpaceForCTE	(	ParseState *	pstate,
		const char *	refname,
		Index *	ctelevelsup
	)

Definition at line 282 of file parse_relation.c.

{
    Index       levelsup;
 
    for (levelsup = 0;
         pstate != NULL;
         pstate = pstate->parentParseState, levelsup++)
    {
        ListCell   *lc;
 
        foreach(lc, pstate->p_ctenamespace)
        {
            CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
 
            if (strcmp(cte->ctename, refname) == 0)
            {
                *ctelevelsup = levelsup;
                return cte;
            }
        }
    }
    return NULL;
}

References CommonTableExpr::ctename, lfirst, ParseState::p_ctenamespace, and ParseState::parentParseState.

Referenced by getNSItemForSpecialRelationTypes(), and searchRangeTableForRel().

scanNameSpaceForENR()

bool scanNameSpaceForENR	(	ParseState *	pstate,
		const char *	refname
	)

Definition at line 335 of file parse_relation.c.

{
    return name_matches_visible_ENR(pstate, refname);
}

References name_matches_visible_ENR().

Referenced by getNSItemForSpecialRelationTypes(), searchRangeTableForRel(), and setTargetTable().

scanNameSpaceForRefname()

static ParseNamespaceItem * scanNameSpaceForRefname ( ParseState *  pstate, const char *  refname, int  location  )

static

Definition at line 200 of file parse_relation.c.

{
    ParseNamespaceItem *result = NULL;
    ListCell   *l;
 
    foreach(l, pstate->p_namespace)
    {
        ParseNamespaceItem *nsitem = (ParseNamespaceItem *) lfirst(l);
 
        /* Ignore columns-only items */
        if (!nsitem->p_rel_visible)
            continue;
        /* If not inside LATERAL, ignore lateral-only items */
        if (nsitem->p_lateral_only && !pstate->p_lateral_active)
            continue;
 
        if (strcmp(nsitem->p_names->aliasname, refname) == 0)
        {
            if (result)
                ereport(ERROR,
                        (errcode(ERRCODE_AMBIGUOUS_ALIAS),
                         errmsg("table reference \"%s\" is ambiguous",
                                refname),
                         parser_errposition(pstate, location)));
            check_lateral_ref_ok(pstate, nsitem, location);
            result = nsitem;
        }
    }
    return result;
}

References Alias::aliasname, check_lateral_ref_ok(), ereport, errcode(), errmsg(), ERROR, lfirst, ParseState::p_lateral_active, ParseNamespaceItem::p_lateral_only, ParseNamespaceItem::p_names, ParseState::p_namespace, ParseNamespaceItem::p_rel_visible, and parser_errposition().

Referenced by refnameNamespaceItem().

scanNameSpaceForRelid()

static ParseNamespaceItem * scanNameSpaceForRelid ( ParseState *  pstate, Oid  relid, int  location  )

static

Definition at line 240 of file parse_relation.c.

{
    ParseNamespaceItem *result = NULL;
    ListCell   *l;
 
    foreach(l, pstate->p_namespace)
    {
        ParseNamespaceItem *nsitem = (ParseNamespaceItem *) lfirst(l);
        RangeTblEntry *rte = nsitem->p_rte;
 
        /* Ignore columns-only items */
        if (!nsitem->p_rel_visible)
            continue;
        /* If not inside LATERAL, ignore lateral-only items */
        if (nsitem->p_lateral_only && !pstate->p_lateral_active)
            continue;
 
        /* yes, the test for alias == NULL should be there... */
        if (rte->rtekind == RTE_RELATION &&
            rte->relid == relid &&
            rte->alias == NULL)
        {
            if (result)
                ereport(ERROR,
                        (errcode(ERRCODE_AMBIGUOUS_ALIAS),
                         errmsg("table reference %u is ambiguous",
                                relid),
                         parser_errposition(pstate, location)));
            check_lateral_ref_ok(pstate, nsitem, location);
            result = nsitem;
        }
    }
    return result;
}

References RangeTblEntry::alias, check_lateral_ref_ok(), ereport, errcode(), errmsg(), ERROR, lfirst, ParseState::p_lateral_active, ParseNamespaceItem::p_lateral_only, ParseState::p_namespace, ParseNamespaceItem::p_rel_visible, ParseNamespaceItem::p_rte, parser_errposition(), RangeTblEntry::relid, RTE_RELATION, and RangeTblEntry::rtekind.

Referenced by refnameNamespaceItem().

scanNSItemForColumn()

Node* scanNSItemForColumn	(	ParseState *	pstate,
		ParseNamespaceItem *	nsitem,
		int	sublevels_up,
		const char *	colname,
		int	location
	)

Definition at line 680 of file parse_relation.c.

{
    RangeTblEntry *rte = nsitem->p_rte;
    int         attnum;
    Var        *var;
 
    /*
     * Scan the nsitem's column names (or aliases) for a match.  Complain if
     * multiple matches.
     */
    attnum = scanRTEForColumn(pstate, rte, nsitem->p_names,
                              colname, location,
                              0, NULL);
 
    if (attnum == InvalidAttrNumber)
        return NULL;            /* Return NULL if no match */
 
    /* In constraint check, no system column is allowed except tableOid */
    if (pstate->p_expr_kind == EXPR_KIND_CHECK_CONSTRAINT &&
        attnum < InvalidAttrNumber && attnum != TableOidAttributeNumber)
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
                 errmsg("system column \"%s\" reference in check constraint is invalid",
                        colname),
                 parser_errposition(pstate, location)));
 
    /* In generated column, no system column is allowed except tableOid */
    if (pstate->p_expr_kind == EXPR_KIND_GENERATED_COLUMN &&
        attnum < InvalidAttrNumber && attnum != TableOidAttributeNumber)
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
                 errmsg("cannot use system column \"%s\" in column generation expression",
                        colname),
                 parser_errposition(pstate, location)));
 
    /*
     * In a MERGE WHEN condition, no system column is allowed except tableOid
     */
    if (pstate->p_expr_kind == EXPR_KIND_MERGE_WHEN &&
        attnum < InvalidAttrNumber && attnum != TableOidAttributeNumber)
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
                 errmsg("cannot use system column \"%s\" in MERGE WHEN condition",
                        colname),
                 parser_errposition(pstate, location)));
 
    /* Found a valid match, so build a Var */
    if (attnum > InvalidAttrNumber)
    {
        /* Get attribute data from the ParseNamespaceColumn array */
        ParseNamespaceColumn *nscol = &nsitem->p_nscolumns[attnum - 1];
 
        /* Complain if dropped column.  See notes in scanRTEForColumn. */
        if (nscol->p_varno == 0)
            ereport(ERROR,
                    (errcode(ERRCODE_UNDEFINED_COLUMN),
                     errmsg("column \"%s\" of relation \"%s\" does not exist",
                            colname,
                            nsitem->p_names->aliasname)));
 
        var = makeVar(nscol->p_varno,
                      nscol->p_varattno,
                      nscol->p_vartype,
                      nscol->p_vartypmod,
                      nscol->p_varcollid,
                      sublevels_up);
        /* makeVar doesn't offer parameters for these, so set them by hand: */
        var->varnosyn = nscol->p_varnosyn;
        var->varattnosyn = nscol->p_varattnosyn;
    }
    else
    {
        /* System column, so use predetermined type data */
        const FormData_pg_attribute *sysatt;
 
        sysatt = SystemAttributeDefinition(attnum);
        var = makeVar(nsitem->p_rtindex,
                      attnum,
                      sysatt->atttypid,
                      sysatt->atttypmod,
                      sysatt->attcollation,
                      sublevels_up);
    }
    var->location = location;
 
    /* Mark Var if it's nulled by any outer joins */
    markNullableIfNeeded(pstate, var);
 
    /* Require read access to the column */
    markVarForSelectPriv(pstate, var);
 
    return (Node *) var;
}

References Alias::aliasname, attnum, ereport, errcode(), errmsg(), ERROR, EXPR_KIND_CHECK_CONSTRAINT, EXPR_KIND_GENERATED_COLUMN, EXPR_KIND_MERGE_WHEN, FormData_pg_attribute, InvalidAttrNumber, Var::location, makeVar(), markNullableIfNeeded(), markVarForSelectPriv(), ParseState::p_expr_kind, ParseNamespaceItem::p_names, ParseNamespaceItem::p_nscolumns, ParseNamespaceItem::p_rte, ParseNamespaceItem::p_rtindex, ParseNamespaceColumn::p_varattno, ParseNamespaceColumn::p_varattnosyn, ParseNamespaceColumn::p_varcollid, ParseNamespaceColumn::p_varno, ParseNamespaceColumn::p_varnosyn, ParseNamespaceColumn::p_vartype, ParseNamespaceColumn::p_vartypmod, parser_errposition(), scanRTEForColumn(), SystemAttributeDefinition(), and TableOidAttributeNumber.

Referenced by colNameToVar(), ParseComplexProjection(), and transformColumnRef().

scanRTEForColumn()

static int scanRTEForColumn ( ParseState *  pstate, RangeTblEntry *  rte, Alias *  eref, const char *  colname, int  location, int  fuzzy_rte_penalty, FuzzyAttrMatchState *  fuzzystate  )

static

Definition at line 800 of file parse_relation.c.

{
    int         result = InvalidAttrNumber;
    int         attnum = 0;
    ListCell   *c;
 
    /*
     * Scan the user column names (or aliases) for a match. Complain if
     * multiple matches.
     *
     * Note: eref->colnames may include entries for dropped columns, but those
     * will be empty strings that cannot match any legal SQL identifier, so we
     * don't bother to test for that case here.
     *
     * Should this somehow go wrong and we try to access a dropped column,
     * we'll still catch it by virtue of the check in scanNSItemForColumn().
     * Callers interested in finding match with shortest distance need to
     * defend against this directly, though.
     */
    foreach(c, eref->colnames)
    {
        const char *attcolname = strVal(lfirst(c));
 
        attnum++;
        if (strcmp(attcolname, colname) == 0)
        {
            if (result)
                ereport(ERROR,
                        (errcode(ERRCODE_AMBIGUOUS_COLUMN),
                         errmsg("column reference \"%s\" is ambiguous",
                                colname),
                         parser_errposition(pstate, location)));
            result = attnum;
        }
 
        /* Update fuzzy match state, if provided. */
        if (fuzzystate != NULL)
            updateFuzzyAttrMatchState(fuzzy_rte_penalty, fuzzystate,
                                      rte, attcolname, colname, attnum);
    }
 
    /*
     * If we have a unique match, return it.  Note that this allows a user
     * alias to override a system column name (such as OID) without error.
     */
    if (result)
        return result;
 
    /*
     * If the RTE represents a real relation, consider system column names.
     * Composites are only used for pseudo-relations like ON CONFLICT's
     * excluded.
     */
    if (rte->rtekind == RTE_RELATION &&
        rte->relkind != RELKIND_COMPOSITE_TYPE)
    {
        /* quick check to see if name could be a system column */
        attnum = specialAttNum(colname);
        if (attnum != InvalidAttrNumber)
        {
            /* now check to see if column actually is defined */
            if (SearchSysCacheExists2(ATTNUM,
                                      ObjectIdGetDatum(rte->relid),
                                      Int16GetDatum(attnum)))
                result = attnum;
        }
    }
 
    return result;
}

References attnum, ATTNUM, Alias::colnames, ereport, errcode(), errmsg(), ERROR, Int16GetDatum(), InvalidAttrNumber, lfirst, ObjectIdGetDatum(), parser_errposition(), RangeTblEntry::relid, RangeTblEntry::relkind, RTE_RELATION, RangeTblEntry::rtekind, SearchSysCacheExists2, specialAttNum(), strVal, and updateFuzzyAttrMatchState().

Referenced by scanNSItemForColumn(), and searchRangeTableForCol().

searchRangeTableForCol()

static FuzzyAttrMatchState* searchRangeTableForCol ( ParseState *  pstate, const char *  alias, const char *  colname, int  location  )

static

Definition at line 952 of file parse_relation.c.

{
    ParseState *orig_pstate = pstate;
    FuzzyAttrMatchState *fuzzystate = palloc(sizeof(FuzzyAttrMatchState));
 
    fuzzystate->distance = MAX_FUZZY_DISTANCE + 1;
    fuzzystate->rfirst = NULL;
    fuzzystate->rsecond = NULL;
    fuzzystate->rexact1 = NULL;
    fuzzystate->rexact2 = NULL;
 
    while (pstate != NULL)
    {
        ListCell   *l;
 
        foreach(l, pstate->p_rtable)
        {
            RangeTblEntry *rte = (RangeTblEntry *) lfirst(l);
            int         fuzzy_rte_penalty = 0;
            int         attnum;
 
            /*
             * Typically, it is not useful to look for matches within join
             * RTEs; they effectively duplicate other RTEs for our purposes,
             * and if a match is chosen from a join RTE, an unhelpful alias is
             * displayed in the final diagnostic message.
             */
            if (rte->rtekind == RTE_JOIN)
                continue;
 
            /*
             * If the user didn't specify an alias, then matches against one
             * RTE are as good as another.  But if the user did specify an
             * alias, then we want at least a fuzzy - and preferably an exact
             * - match for the range table entry.
             */
            if (alias != NULL)
                fuzzy_rte_penalty =
                    varstr_levenshtein_less_equal(alias, strlen(alias),
                                                  rte->eref->aliasname,
                                                  strlen(rte->eref->aliasname),
                                                  1, 1, 1,
                                                  MAX_FUZZY_DISTANCE + 1,
                                                  true);
 
            /*
             * Scan for a matching column, and update fuzzystate.  Non-exact
             * matches are dealt with inside scanRTEForColumn, but exact
             * matches are handled here.  (There won't be more than one exact
             * match in the same RTE, else we'd have thrown error earlier.)
             */
            attnum = scanRTEForColumn(orig_pstate, rte, rte->eref,
                                      colname, location,
                                      fuzzy_rte_penalty, fuzzystate);
            if (attnum != InvalidAttrNumber && fuzzy_rte_penalty == 0)
            {
                if (fuzzystate->rexact1 == NULL)
                {
                    fuzzystate->rexact1 = rte;
                    fuzzystate->exact1 = attnum;
                }
                else
                {
                    /* Needn't worry about overwriting previous rexact2 */
                    fuzzystate->rexact2 = rte;
                    fuzzystate->exact2 = attnum;
                }
            }
        }
 
        pstate = pstate->parentParseState;
    }
 
    return fuzzystate;
}

References Alias::aliasname, attnum, FuzzyAttrMatchState::distance, RangeTblEntry::eref, FuzzyAttrMatchState::exact1, FuzzyAttrMatchState::exact2, InvalidAttrNumber, lfirst, MAX_FUZZY_DISTANCE, ParseState::p_rtable, palloc(), ParseState::parentParseState, FuzzyAttrMatchState::rexact1, FuzzyAttrMatchState::rexact2, FuzzyAttrMatchState::rfirst, FuzzyAttrMatchState::rsecond, RTE_JOIN, RangeTblEntry::rtekind, scanRTEForColumn(), and varstr_levenshtein_less_equal().

Referenced by errorMissingColumn().

searchRangeTableForRel()

static RangeTblEntry* searchRangeTableForRel ( ParseState *  pstate, RangeVar *  relation  )

static

Definition at line 356 of file parse_relation.c.

{
    const char *refname = relation->relname;
    Oid         relId = InvalidOid;
    CommonTableExpr *cte = NULL;
    bool        isenr = false;
    Index       ctelevelsup = 0;
    Index       levelsup;
 
    /*
     * If it's an unqualified name, check for possible CTE matches. A CTE
     * hides any real relation matches.  If no CTE, look for a matching
     * relation.
     *
     * NB: It's not critical that RangeVarGetRelid return the correct answer
     * here in the face of concurrent DDL.  If it doesn't, the worst case
     * scenario is a less-clear error message.  Also, the tables involved in
     * the query are already locked, which reduces the number of cases in
     * which surprising behavior can occur.  So we do the name lookup
     * unlocked.
     */
    if (!relation->schemaname)
    {
        cte = scanNameSpaceForCTE(pstate, refname, &ctelevelsup);
        if (!cte)
            isenr = scanNameSpaceForENR(pstate, refname);
    }
 
    if (!cte && !isenr)
        relId = RangeVarGetRelid(relation, NoLock, true);
 
    /* Now look for RTEs matching either the relation/CTE/ENR or the alias */
    for (levelsup = 0;
         pstate != NULL;
         pstate = pstate->parentParseState, levelsup++)
    {
        ListCell   *l;
 
        foreach(l, pstate->p_rtable)
        {
            RangeTblEntry *rte = (RangeTblEntry *) lfirst(l);
 
            if (rte->rtekind == RTE_RELATION &&
                OidIsValid(relId) &&
                rte->relid == relId)
                return rte;
            if (rte->rtekind == RTE_CTE &&
                cte != NULL &&
                rte->ctelevelsup + levelsup == ctelevelsup &&
                strcmp(rte->ctename, refname) == 0)
                return rte;
            if (rte->rtekind == RTE_NAMEDTUPLESTORE &&
                isenr &&
                strcmp(rte->enrname, refname) == 0)
                return rte;
            if (strcmp(rte->eref->aliasname, refname) == 0)
                return rte;
        }
    }
    return NULL;
}

References Alias::aliasname, RangeTblEntry::ctelevelsup, RangeTblEntry::ctename, RangeTblEntry::enrname, RangeTblEntry::eref, InvalidOid, lfirst, NoLock, OidIsValid, ParseState::p_rtable, ParseState::parentParseState, RangeVarGetRelid, RangeTblEntry::relid, RangeVar::relname, RTE_CTE, RTE_NAMEDTUPLESTORE, RTE_RELATION, RangeTblEntry::rtekind, scanNameSpaceForCTE(), scanNameSpaceForENR(), and RangeVar::schemaname.

Referenced by errorMissingRTE().

specialAttNum()

static int specialAttNum ( const char *  attname )

static

Definition at line 3511 of file parse_relation.c.

{
    const FormData_pg_attribute *sysatt;
 
    sysatt = SystemAttributeByName(attname);
    if (sysatt != NULL)
        return sysatt->attnum;
    return InvalidAttrNumber;
}

References attname, FormData_pg_attribute, InvalidAttrNumber, and SystemAttributeByName().

Referenced by attnameAttNum(), and scanRTEForColumn().

updateFuzzyAttrMatchState()

static void updateFuzzyAttrMatchState ( int  fuzzy_rte_penalty, FuzzyAttrMatchState *  fuzzystate, RangeTblEntry *  rte, const char *  actual, const char *  match, int  attnum  )

static

Definition at line 587 of file parse_relation.c.

{
    int         columndistance;
    int         matchlen;
 
    /* Bail before computing the Levenshtein distance if there's no hope. */
    if (fuzzy_rte_penalty > fuzzystate->distance)
        return;
 
    /*
     * Outright reject dropped columns, which can appear here with apparent
     * empty actual names, per remarks within scanRTEForColumn().
     */
    if (actual[0] == '\0')
        return;
 
    /* Use Levenshtein to compute match distance. */
    matchlen = strlen(match);
    columndistance =
        varstr_levenshtein_less_equal(actual, strlen(actual), match, matchlen,
                                      1, 1, 1,
                                      fuzzystate->distance + 1
                                      - fuzzy_rte_penalty,
                                      true);
 
    /*
     * If more than half the characters are different, don't treat it as a
     * match, to avoid making ridiculous suggestions.
     */
    if (columndistance > matchlen / 2)
        return;
 
    /*
     * From this point on, we can ignore the distinction between the RTE-name
     * distance and the column-name distance.
     */
    columndistance += fuzzy_rte_penalty;
 
    /*
     * If the new distance is less than or equal to that of the best match
     * found so far, update fuzzystate.
     */
    if (columndistance < fuzzystate->distance)
    {
        /* Store new lowest observed distance as first/only match */
        fuzzystate->distance = columndistance;
        fuzzystate->rfirst = rte;
        fuzzystate->first = attnum;
        fuzzystate->rsecond = NULL;
    }
    else if (columndistance == fuzzystate->distance)
    {
        /* If we already have a match of this distance, update state */
        if (fuzzystate->rsecond != NULL)
        {
            /*
             * Too many matches at same distance.  Clearly, this value of
             * distance is too low a bar, so drop these entries while keeping
             * the current distance value, so that only smaller distances will
             * be considered interesting.  Only if we find something of lower
             * distance will we re-populate rfirst (via the stanza above).
             */
            fuzzystate->rfirst = NULL;
            fuzzystate->rsecond = NULL;
        }
        else if (fuzzystate->rfirst != NULL)
        {
            /* Record as provisional second match */
            fuzzystate->rsecond = rte;
            fuzzystate->second = attnum;
        }
        else
        {
            /*
             * Do nothing.  When rfirst is NULL, distance is more than what we
             * want to consider acceptable, so we should ignore this match.
             */
        }
    }
}

References attnum, FuzzyAttrMatchState::distance, FuzzyAttrMatchState::first, FuzzyAttrMatchState::rfirst, FuzzyAttrMatchState::rsecond, FuzzyAttrMatchState::second, and varstr_levenshtein_less_equal().

Referenced by scanRTEForColumn().