3647 lines
111 KiB
C
3647 lines
111 KiB
C
/*-------------------------------------------------------------------------
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*
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* parse_clause.c
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* handle clauses in parser
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*
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* Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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*
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* IDENTIFICATION
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* src/backend/parser/parse_clause.c
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include "access/htup_details.h"
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#include "access/nbtree.h"
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#include "access/table.h"
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#include "access/tsmapi.h"
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#include "catalog/catalog.h"
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#include "catalog/heap.h"
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#include "catalog/pg_am.h"
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#include "catalog/pg_amproc.h"
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#include "catalog/pg_collation.h"
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#include "catalog/pg_constraint.h"
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#include "catalog/pg_type.h"
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#include "commands/defrem.h"
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#include "miscadmin.h"
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#include "nodes/makefuncs.h"
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#include "nodes/nodeFuncs.h"
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#include "optimizer/optimizer.h"
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#include "parser/analyze.h"
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#include "parser/parse_clause.h"
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#include "parser/parse_coerce.h"
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#include "parser/parse_collate.h"
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#include "parser/parse_expr.h"
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#include "parser/parse_func.h"
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#include "parser/parse_oper.h"
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#include "parser/parse_relation.h"
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#include "parser/parse_target.h"
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#include "parser/parse_type.h"
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#include "parser/parser.h"
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#include "parser/parsetree.h"
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#include "rewrite/rewriteManip.h"
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#include "utils/builtins.h"
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#include "utils/catcache.h"
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#include "utils/guc.h"
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#include "utils/lsyscache.h"
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#include "utils/rel.h"
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#include "utils/syscache.h"
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/* Convenience macro for the most common makeNamespaceItem() case */
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#define makeDefaultNSItem(rte) makeNamespaceItem(rte, true, true, false, true)
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static void extractRemainingColumns(List *common_colnames,
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List *src_colnames, List *src_colvars,
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List **res_colnames, List **res_colvars);
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static Node *transformJoinUsingClause(ParseState *pstate,
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RangeTblEntry *leftRTE, RangeTblEntry *rightRTE,
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List *leftVars, List *rightVars);
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static Node *transformJoinOnClause(ParseState *pstate, JoinExpr *j,
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List *namespace);
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static RangeTblEntry *getRTEForSpecialRelationTypes(ParseState *pstate,
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RangeVar *rv);
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static RangeTblEntry *transformTableEntry(ParseState *pstate, RangeVar *r);
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static RangeTblEntry *transformRangeSubselect(ParseState *pstate,
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RangeSubselect *r);
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static RangeTblEntry *transformRangeFunction(ParseState *pstate,
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RangeFunction *r);
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static RangeTblEntry *transformRangeTableFunc(ParseState *pstate,
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RangeTableFunc *t);
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static TableSampleClause *transformRangeTableSample(ParseState *pstate,
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RangeTableSample *rts);
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static Node *transformFromClauseItem(ParseState *pstate, Node *n,
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RangeTblEntry **top_rte, int *top_rti,
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List **namespace);
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static Node *buildMergedJoinVar(ParseState *pstate, JoinType jointype,
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Var *l_colvar, Var *r_colvar);
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static ParseNamespaceItem *makeNamespaceItem(RangeTblEntry *rte,
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bool rel_visible, bool cols_visible,
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bool lateral_only, bool lateral_ok);
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static void setNamespaceColumnVisibility(List *namespace, bool cols_visible);
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static void setNamespaceLateralState(List *namespace,
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bool lateral_only, bool lateral_ok);
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static void checkExprIsVarFree(ParseState *pstate, Node *n,
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const char *constructName);
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static TargetEntry *findTargetlistEntrySQL92(ParseState *pstate, Node *node,
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List **tlist, ParseExprKind exprKind);
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static TargetEntry *findTargetlistEntrySQL99(ParseState *pstate, Node *node,
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List **tlist, ParseExprKind exprKind);
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static int get_matching_location(int sortgroupref,
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List *sortgrouprefs, List *exprs);
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static List *resolve_unique_index_expr(ParseState *pstate, InferClause *infer,
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Relation heapRel);
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static List *addTargetToGroupList(ParseState *pstate, TargetEntry *tle,
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List *grouplist, List *targetlist, int location);
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static WindowClause *findWindowClause(List *wclist, const char *name);
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static Node *transformFrameOffset(ParseState *pstate, int frameOptions,
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Oid rangeopfamily, Oid rangeopcintype, Oid *inRangeFunc,
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Node *clause);
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/*
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* transformFromClause -
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* Process the FROM clause and add items to the query's range table,
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* joinlist, and namespace.
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*
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* Note: we assume that the pstate's p_rtable, p_joinlist, and p_namespace
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* lists were initialized to NIL when the pstate was created.
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* We will add onto any entries already present --- this is needed for rule
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* processing, as well as for UPDATE and DELETE.
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*/
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void
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transformFromClause(ParseState *pstate, List *frmList)
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{
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ListCell *fl;
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/*
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* The grammar will have produced a list of RangeVars, RangeSubselects,
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* RangeFunctions, and/or JoinExprs. Transform each one (possibly adding
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* entries to the rtable), check for duplicate refnames, and then add it
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* to the joinlist and namespace.
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*
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* Note we must process the items left-to-right for proper handling of
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* LATERAL references.
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*/
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foreach(fl, frmList)
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{
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Node *n = lfirst(fl);
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RangeTblEntry *rte;
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int rtindex;
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List *namespace;
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n = transformFromClauseItem(pstate, n,
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&rte,
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&rtindex,
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&namespace);
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checkNameSpaceConflicts(pstate, pstate->p_namespace, namespace);
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/* Mark the new namespace items as visible only to LATERAL */
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setNamespaceLateralState(namespace, true, true);
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pstate->p_joinlist = lappend(pstate->p_joinlist, n);
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pstate->p_namespace = list_concat(pstate->p_namespace, namespace);
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}
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/*
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* We're done parsing the FROM list, so make all namespace items
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* unconditionally visible. Note that this will also reset lateral_only
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* for any namespace items that were already present when we were called;
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* but those should have been that way already.
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*/
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setNamespaceLateralState(pstate->p_namespace, false, true);
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}
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/*
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* setTargetTable
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* Add the target relation of INSERT/UPDATE/DELETE to the range table,
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* and make the special links to it in the ParseState.
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*
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* We also open the target relation and acquire a write lock on it.
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* This must be done before processing the FROM list, in case the target
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* is also mentioned as a source relation --- we want to be sure to grab
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* the write lock before any read lock.
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*
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* If alsoSource is true, add the target to the query's joinlist and
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* namespace. For INSERT, we don't want the target to be joined to;
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* it's a destination of tuples, not a source. For UPDATE/DELETE,
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* we do need to scan or join the target. (NOTE: we do not bother
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* to check for namespace conflict; we assume that the namespace was
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* initially empty in these cases.)
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*
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* Finally, we mark the relation as requiring the permissions specified
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* by requiredPerms.
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*
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* Returns the rangetable index of the target relation.
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*/
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int
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setTargetTable(ParseState *pstate, RangeVar *relation,
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bool inh, bool alsoSource, AclMode requiredPerms)
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{
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RangeTblEntry *rte;
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int rtindex;
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/*
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* ENRs hide tables of the same name, so we need to check for them first.
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* In contrast, CTEs don't hide tables (for this purpose).
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*/
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if (relation->schemaname == NULL &&
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scanNameSpaceForENR(pstate, relation->relname))
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ereport(ERROR,
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(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
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errmsg("relation \"%s\" cannot be the target of a modifying statement",
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relation->relname)));
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/* Close old target; this could only happen for multi-action rules */
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if (pstate->p_target_relation != NULL)
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table_close(pstate->p_target_relation, NoLock);
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/*
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* Open target rel and grab suitable lock (which we will hold till end of
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* transaction).
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*
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* free_parsestate() will eventually do the corresponding table_close(),
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* but *not* release the lock.
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*/
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pstate->p_target_relation = parserOpenTable(pstate, relation,
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RowExclusiveLock);
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/*
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* Now build an RTE.
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*/
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rte = addRangeTableEntryForRelation(pstate, pstate->p_target_relation,
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RowExclusiveLock,
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relation->alias, inh, false);
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pstate->p_target_rangetblentry = rte;
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/* assume new rte is at end */
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rtindex = list_length(pstate->p_rtable);
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Assert(rte == rt_fetch(rtindex, pstate->p_rtable));
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/*
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* Override addRangeTableEntry's default ACL_SELECT permissions check, and
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* instead mark target table as requiring exactly the specified
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* permissions.
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*
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* If we find an explicit reference to the rel later during parse
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* analysis, we will add the ACL_SELECT bit back again; see
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* markVarForSelectPriv and its callers.
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*/
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rte->requiredPerms = requiredPerms;
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/*
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* If UPDATE/DELETE, add table to joinlist and namespace.
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*
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* Note: some callers know that they can find the new ParseNamespaceItem
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* at the end of the pstate->p_namespace list. This is a bit ugly but not
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* worth complicating this function's signature for.
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*/
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if (alsoSource)
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addRTEtoQuery(pstate, rte, true, true, true);
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return rtindex;
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}
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/*
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* Extract all not-in-common columns from column lists of a source table
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*/
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static void
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extractRemainingColumns(List *common_colnames,
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List *src_colnames, List *src_colvars,
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List **res_colnames, List **res_colvars)
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{
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List *new_colnames = NIL;
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List *new_colvars = NIL;
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ListCell *lnames,
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*lvars;
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Assert(list_length(src_colnames) == list_length(src_colvars));
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forboth(lnames, src_colnames, lvars, src_colvars)
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{
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char *colname = strVal(lfirst(lnames));
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bool match = false;
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ListCell *cnames;
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foreach(cnames, common_colnames)
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{
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char *ccolname = strVal(lfirst(cnames));
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if (strcmp(colname, ccolname) == 0)
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{
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match = true;
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break;
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}
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}
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if (!match)
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{
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new_colnames = lappend(new_colnames, lfirst(lnames));
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new_colvars = lappend(new_colvars, lfirst(lvars));
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}
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}
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*res_colnames = new_colnames;
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*res_colvars = new_colvars;
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}
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/* transformJoinUsingClause()
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* Build a complete ON clause from a partially-transformed USING list.
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* We are given lists of nodes representing left and right match columns.
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* Result is a transformed qualification expression.
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*/
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static Node *
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transformJoinUsingClause(ParseState *pstate,
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RangeTblEntry *leftRTE, RangeTblEntry *rightRTE,
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List *leftVars, List *rightVars)
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{
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Node *result;
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List *andargs = NIL;
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ListCell *lvars,
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*rvars;
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/*
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* We cheat a little bit here by building an untransformed operator tree
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* whose leaves are the already-transformed Vars. This requires collusion
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* from transformExpr(), which normally could be expected to complain
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* about already-transformed subnodes. However, this does mean that we
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* have to mark the columns as requiring SELECT privilege for ourselves;
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* transformExpr() won't do it.
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*/
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forboth(lvars, leftVars, rvars, rightVars)
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{
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Var *lvar = (Var *) lfirst(lvars);
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Var *rvar = (Var *) lfirst(rvars);
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A_Expr *e;
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/* Require read access to the join variables */
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markVarForSelectPriv(pstate, lvar, leftRTE);
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markVarForSelectPriv(pstate, rvar, rightRTE);
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/* Now create the lvar = rvar join condition */
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e = makeSimpleA_Expr(AEXPR_OP, "=",
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(Node *) copyObject(lvar), (Node *) copyObject(rvar),
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-1);
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/* Prepare to combine into an AND clause, if multiple join columns */
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andargs = lappend(andargs, e);
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}
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/* Only need an AND if there's more than one join column */
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if (list_length(andargs) == 1)
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result = (Node *) linitial(andargs);
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else
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result = (Node *) makeBoolExpr(AND_EXPR, andargs, -1);
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/*
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* Since the references are already Vars, and are certainly from the input
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* relations, we don't have to go through the same pushups that
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* transformJoinOnClause() does. Just invoke transformExpr() to fix up
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* the operators, and we're done.
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*/
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result = transformExpr(pstate, result, EXPR_KIND_JOIN_USING);
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result = coerce_to_boolean(pstate, result, "JOIN/USING");
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return result;
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}
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/* transformJoinOnClause()
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* Transform the qual conditions for JOIN/ON.
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* Result is a transformed qualification expression.
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*/
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static Node *
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transformJoinOnClause(ParseState *pstate, JoinExpr *j, List *namespace)
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{
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Node *result;
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List *save_namespace;
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/*
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* The namespace that the join expression should see is just the two
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* subtrees of the JOIN plus any outer references from upper pstate
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* levels. Temporarily set this pstate's namespace accordingly. (We need
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* not check for refname conflicts, because transformFromClauseItem()
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* already did.) All namespace items are marked visible regardless of
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* LATERAL state.
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*/
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setNamespaceLateralState(namespace, false, true);
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save_namespace = pstate->p_namespace;
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pstate->p_namespace = namespace;
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result = transformWhereClause(pstate, j->quals,
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EXPR_KIND_JOIN_ON, "JOIN/ON");
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pstate->p_namespace = save_namespace;
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return result;
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}
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/*
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* transformTableEntry --- transform a RangeVar (simple relation reference)
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*/
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static RangeTblEntry *
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transformTableEntry(ParseState *pstate, RangeVar *r)
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{
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RangeTblEntry *rte;
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/* We need only build a range table entry */
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rte = addRangeTableEntry(pstate, r, r->alias, r->inh, true);
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return rte;
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}
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/*
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* transformRangeSubselect --- transform a sub-SELECT appearing in FROM
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*/
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static RangeTblEntry *
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transformRangeSubselect(ParseState *pstate, RangeSubselect *r)
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{
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Query *query;
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RangeTblEntry *rte;
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/*
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* We require user to supply an alias for a subselect, per SQL92. To relax
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* this, we'd have to be prepared to gin up a unique alias for an
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* unlabeled subselect. (This is just elog, not ereport, because the
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* grammar should have enforced it already. It'd probably be better to
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* report the error here, but we don't have a good error location here.)
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*/
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if (r->alias == NULL)
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elog(ERROR, "subquery in FROM must have an alias");
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/*
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* Set p_expr_kind to show this parse level is recursing to a subselect.
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* We can't be nested within any expression, so don't need save-restore
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* logic here.
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*/
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Assert(pstate->p_expr_kind == EXPR_KIND_NONE);
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pstate->p_expr_kind = EXPR_KIND_FROM_SUBSELECT;
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/*
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* If the subselect is LATERAL, make lateral_only names of this level
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* visible to it. (LATERAL can't nest within a single pstate level, so we
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* don't need save/restore logic here.)
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*/
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Assert(!pstate->p_lateral_active);
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pstate->p_lateral_active = r->lateral;
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/*
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* Analyze and transform the subquery.
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*/
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query = parse_sub_analyze(r->subquery, pstate, NULL,
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isLockedRefname(pstate, r->alias->aliasname),
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true);
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/* Restore state */
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pstate->p_lateral_active = false;
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pstate->p_expr_kind = EXPR_KIND_NONE;
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/*
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* Check that we got a SELECT. Anything else should be impossible given
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* restrictions of the grammar, but check anyway.
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*/
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if (!IsA(query, Query) ||
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query->commandType != CMD_SELECT)
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elog(ERROR, "unexpected non-SELECT command in subquery in FROM");
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/*
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* OK, build an RTE for the subquery.
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*/
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rte = addRangeTableEntryForSubquery(pstate,
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query,
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r->alias,
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r->lateral,
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true);
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return rte;
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}
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/*
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* transformRangeFunction --- transform a function call appearing in FROM
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*/
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static RangeTblEntry *
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transformRangeFunction(ParseState *pstate, RangeFunction *r)
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{
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List *funcexprs = NIL;
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List *funcnames = NIL;
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List *coldeflists = NIL;
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bool is_lateral;
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RangeTblEntry *rte;
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ListCell *lc;
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/*
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* We make lateral_only names of this level visible, whether or not the
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* RangeFunction is explicitly marked LATERAL. This is needed for SQL
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* spec compliance in the case of UNNEST(), and seems useful on
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* convenience grounds for all functions in FROM.
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*
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* (LATERAL can't nest within a single pstate level, so we don't need
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* save/restore logic here.)
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*/
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Assert(!pstate->p_lateral_active);
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pstate->p_lateral_active = true;
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/*
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* Transform the raw expressions.
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*
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* While transforming, also save function names for possible use as alias
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* and column names. We use the same transformation rules as for a SELECT
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* output expression. For a FuncCall node, the result will be the
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* function name, but it is possible for the grammar to hand back other
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* node types.
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*
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* We have to get this info now, because FigureColname only works on raw
|
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* parsetrees. Actually deciding what to do with the names is left up to
|
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* addRangeTableEntryForFunction.
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*
|
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* Likewise, collect column definition lists if there were any. But
|
|
* complain if we find one here and the RangeFunction has one too.
|
|
*/
|
|
foreach(lc, r->functions)
|
|
{
|
|
List *pair = (List *) lfirst(lc);
|
|
Node *fexpr;
|
|
List *coldeflist;
|
|
Node *newfexpr;
|
|
Node *last_srf;
|
|
|
|
/* Disassemble the function-call/column-def-list pairs */
|
|
Assert(list_length(pair) == 2);
|
|
fexpr = (Node *) linitial(pair);
|
|
coldeflist = (List *) lsecond(pair);
|
|
|
|
/*
|
|
* If we find a function call unnest() with more than one argument and
|
|
* no special decoration, transform it into separate unnest() calls on
|
|
* each argument. This is a kluge, for sure, but it's less nasty than
|
|
* other ways of implementing the SQL-standard UNNEST() syntax.
|
|
*
|
|
* If there is any decoration (including a coldeflist), we don't
|
|
* transform, which probably means a no-such-function error later. We
|
|
* could alternatively throw an error right now, but that doesn't seem
|
|
* tremendously helpful. If someone is using any such decoration,
|
|
* then they're not using the SQL-standard syntax, and they're more
|
|
* likely expecting an un-tweaked function call.
|
|
*
|
|
* Note: the transformation changes a non-schema-qualified unnest()
|
|
* function name into schema-qualified pg_catalog.unnest(). This
|
|
* choice is also a bit debatable, but it seems reasonable to force
|
|
* use of built-in unnest() when we make this transformation.
|
|
*/
|
|
if (IsA(fexpr, FuncCall))
|
|
{
|
|
FuncCall *fc = (FuncCall *) fexpr;
|
|
|
|
if (list_length(fc->funcname) == 1 &&
|
|
strcmp(strVal(linitial(fc->funcname)), "unnest") == 0 &&
|
|
list_length(fc->args) > 1 &&
|
|
fc->agg_order == NIL &&
|
|
fc->agg_filter == NULL &&
|
|
!fc->agg_star &&
|
|
!fc->agg_distinct &&
|
|
!fc->func_variadic &&
|
|
fc->over == NULL &&
|
|
coldeflist == NIL)
|
|
{
|
|
ListCell *lc;
|
|
|
|
foreach(lc, fc->args)
|
|
{
|
|
Node *arg = (Node *) lfirst(lc);
|
|
FuncCall *newfc;
|
|
|
|
last_srf = pstate->p_last_srf;
|
|
|
|
newfc = makeFuncCall(SystemFuncName("unnest"),
|
|
list_make1(arg),
|
|
fc->location);
|
|
|
|
newfexpr = transformExpr(pstate, (Node *) newfc,
|
|
EXPR_KIND_FROM_FUNCTION);
|
|
|
|
/* nodeFunctionscan.c requires SRFs to be at top level */
|
|
if (pstate->p_last_srf != last_srf &&
|
|
pstate->p_last_srf != newfexpr)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("set-returning functions must appear at top level of FROM"),
|
|
parser_errposition(pstate,
|
|
exprLocation(pstate->p_last_srf))));
|
|
|
|
funcexprs = lappend(funcexprs, newfexpr);
|
|
|
|
funcnames = lappend(funcnames,
|
|
FigureColname((Node *) newfc));
|
|
|
|
/* coldeflist is empty, so no error is possible */
|
|
|
|
coldeflists = lappend(coldeflists, coldeflist);
|
|
}
|
|
continue; /* done with this function item */
|
|
}
|
|
}
|
|
|
|
/* normal case ... */
|
|
last_srf = pstate->p_last_srf;
|
|
|
|
newfexpr = transformExpr(pstate, fexpr,
|
|
EXPR_KIND_FROM_FUNCTION);
|
|
|
|
/* nodeFunctionscan.c requires SRFs to be at top level */
|
|
if (pstate->p_last_srf != last_srf &&
|
|
pstate->p_last_srf != newfexpr)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("set-returning functions must appear at top level of FROM"),
|
|
parser_errposition(pstate,
|
|
exprLocation(pstate->p_last_srf))));
|
|
|
|
funcexprs = lappend(funcexprs, newfexpr);
|
|
|
|
funcnames = lappend(funcnames,
|
|
FigureColname(fexpr));
|
|
|
|
if (coldeflist && r->coldeflist)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("multiple column definition lists are not allowed for the same function"),
|
|
parser_errposition(pstate,
|
|
exprLocation((Node *) r->coldeflist))));
|
|
|
|
coldeflists = lappend(coldeflists, coldeflist);
|
|
}
|
|
|
|
pstate->p_lateral_active = false;
|
|
|
|
/*
|
|
* We must assign collations now so that the RTE exposes correct collation
|
|
* info for Vars created from it.
|
|
*/
|
|
assign_list_collations(pstate, funcexprs);
|
|
|
|
/*
|
|
* Install the top-level coldeflist if there was one (we already checked
|
|
* that there was no conflicting per-function coldeflist).
|
|
*
|
|
* We only allow this when there's a single function (even after UNNEST
|
|
* expansion) and no WITH ORDINALITY. The reason for the latter
|
|
* restriction is that it's not real clear whether the ordinality column
|
|
* should be in the coldeflist, and users are too likely to make mistakes
|
|
* in one direction or the other. Putting the coldeflist inside ROWS
|
|
* FROM() is much clearer in this case.
|
|
*/
|
|
if (r->coldeflist)
|
|
{
|
|
if (list_length(funcexprs) != 1)
|
|
{
|
|
if (r->is_rowsfrom)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("ROWS FROM() with multiple functions cannot have a column definition list"),
|
|
errhint("Put a separate column definition list for each function inside ROWS FROM()."),
|
|
parser_errposition(pstate,
|
|
exprLocation((Node *) r->coldeflist))));
|
|
else
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("UNNEST() with multiple arguments cannot have a column definition list"),
|
|
errhint("Use separate UNNEST() calls inside ROWS FROM(), and attach a column definition list to each one."),
|
|
parser_errposition(pstate,
|
|
exprLocation((Node *) r->coldeflist))));
|
|
}
|
|
if (r->ordinality)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("WITH ORDINALITY cannot be used with a column definition list"),
|
|
errhint("Put the column definition list inside ROWS FROM()."),
|
|
parser_errposition(pstate,
|
|
exprLocation((Node *) r->coldeflist))));
|
|
|
|
coldeflists = list_make1(r->coldeflist);
|
|
}
|
|
|
|
/*
|
|
* Mark the RTE as LATERAL if the user said LATERAL explicitly, or if
|
|
* there are any lateral cross-references in it.
|
|
*/
|
|
is_lateral = r->lateral || contain_vars_of_level((Node *) funcexprs, 0);
|
|
|
|
/*
|
|
* OK, build an RTE for the function.
|
|
*/
|
|
rte = addRangeTableEntryForFunction(pstate,
|
|
funcnames, funcexprs, coldeflists,
|
|
r, is_lateral, true);
|
|
|
|
return rte;
|
|
}
|
|
|
|
/*
|
|
* transformRangeTableFunc -
|
|
* Transform a raw RangeTableFunc into TableFunc.
|
|
*
|
|
* Transform the namespace clauses, the document-generating expression, the
|
|
* row-generating expression, the column-generating expressions, and the
|
|
* default value expressions.
|
|
*/
|
|
static RangeTblEntry *
|
|
transformRangeTableFunc(ParseState *pstate, RangeTableFunc *rtf)
|
|
{
|
|
TableFunc *tf = makeNode(TableFunc);
|
|
const char *constructName;
|
|
Oid docType;
|
|
RangeTblEntry *rte;
|
|
bool is_lateral;
|
|
ListCell *col;
|
|
char **names;
|
|
int colno;
|
|
|
|
/* Currently only XMLTABLE is supported */
|
|
constructName = "XMLTABLE";
|
|
docType = XMLOID;
|
|
|
|
/*
|
|
* We make lateral_only names of this level visible, whether or not the
|
|
* RangeTableFunc is explicitly marked LATERAL. This is needed for SQL
|
|
* spec compliance and seems useful on convenience grounds for all
|
|
* functions in FROM.
|
|
*
|
|
* (LATERAL can't nest within a single pstate level, so we don't need
|
|
* save/restore logic here.)
|
|
*/
|
|
Assert(!pstate->p_lateral_active);
|
|
pstate->p_lateral_active = true;
|
|
|
|
/* Transform and apply typecast to the row-generating expression ... */
|
|
Assert(rtf->rowexpr != NULL);
|
|
tf->rowexpr = coerce_to_specific_type(pstate,
|
|
transformExpr(pstate, rtf->rowexpr, EXPR_KIND_FROM_FUNCTION),
|
|
TEXTOID,
|
|
constructName);
|
|
assign_expr_collations(pstate, tf->rowexpr);
|
|
|
|
/* ... and to the document itself */
|
|
Assert(rtf->docexpr != NULL);
|
|
tf->docexpr = coerce_to_specific_type(pstate,
|
|
transformExpr(pstate, rtf->docexpr, EXPR_KIND_FROM_FUNCTION),
|
|
docType,
|
|
constructName);
|
|
assign_expr_collations(pstate, tf->docexpr);
|
|
|
|
/* undef ordinality column number */
|
|
tf->ordinalitycol = -1;
|
|
|
|
/* Process column specs */
|
|
names = palloc(sizeof(char *) * list_length(rtf->columns));
|
|
|
|
colno = 0;
|
|
foreach(col, rtf->columns)
|
|
{
|
|
RangeTableFuncCol *rawc = (RangeTableFuncCol *) lfirst(col);
|
|
Oid typid;
|
|
int32 typmod;
|
|
Node *colexpr;
|
|
Node *coldefexpr;
|
|
int j;
|
|
|
|
tf->colnames = lappend(tf->colnames,
|
|
makeString(pstrdup(rawc->colname)));
|
|
|
|
/*
|
|
* Determine the type and typmod for the new column. FOR ORDINALITY
|
|
* columns are INTEGER per spec; the others are user-specified.
|
|
*/
|
|
if (rawc->for_ordinality)
|
|
{
|
|
if (tf->ordinalitycol != -1)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("only one FOR ORDINALITY column is allowed"),
|
|
parser_errposition(pstate, rawc->location)));
|
|
|
|
typid = INT4OID;
|
|
typmod = -1;
|
|
tf->ordinalitycol = colno;
|
|
}
|
|
else
|
|
{
|
|
if (rawc->typeName->setof)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
|
|
errmsg("column \"%s\" cannot be declared SETOF",
|
|
rawc->colname),
|
|
parser_errposition(pstate, rawc->location)));
|
|
|
|
typenameTypeIdAndMod(pstate, rawc->typeName,
|
|
&typid, &typmod);
|
|
}
|
|
|
|
tf->coltypes = lappend_oid(tf->coltypes, typid);
|
|
tf->coltypmods = lappend_int(tf->coltypmods, typmod);
|
|
tf->colcollations = lappend_oid(tf->colcollations,
|
|
get_typcollation(typid));
|
|
|
|
/* Transform the PATH and DEFAULT expressions */
|
|
if (rawc->colexpr)
|
|
{
|
|
colexpr = coerce_to_specific_type(pstate,
|
|
transformExpr(pstate, rawc->colexpr,
|
|
EXPR_KIND_FROM_FUNCTION),
|
|
TEXTOID,
|
|
constructName);
|
|
assign_expr_collations(pstate, colexpr);
|
|
}
|
|
else
|
|
colexpr = NULL;
|
|
|
|
if (rawc->coldefexpr)
|
|
{
|
|
coldefexpr = coerce_to_specific_type_typmod(pstate,
|
|
transformExpr(pstate, rawc->coldefexpr,
|
|
EXPR_KIND_FROM_FUNCTION),
|
|
typid, typmod,
|
|
constructName);
|
|
assign_expr_collations(pstate, coldefexpr);
|
|
}
|
|
else
|
|
coldefexpr = NULL;
|
|
|
|
tf->colexprs = lappend(tf->colexprs, colexpr);
|
|
tf->coldefexprs = lappend(tf->coldefexprs, coldefexpr);
|
|
|
|
if (rawc->is_not_null)
|
|
tf->notnulls = bms_add_member(tf->notnulls, colno);
|
|
|
|
/* make sure column names are unique */
|
|
for (j = 0; j < colno; j++)
|
|
if (strcmp(names[j], rawc->colname) == 0)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("column name \"%s\" is not unique",
|
|
rawc->colname),
|
|
parser_errposition(pstate, rawc->location)));
|
|
names[colno] = rawc->colname;
|
|
|
|
colno++;
|
|
}
|
|
pfree(names);
|
|
|
|
/* Namespaces, if any, also need to be transformed */
|
|
if (rtf->namespaces != NIL)
|
|
{
|
|
ListCell *ns;
|
|
ListCell *lc2;
|
|
List *ns_uris = NIL;
|
|
List *ns_names = NIL;
|
|
bool default_ns_seen = false;
|
|
|
|
foreach(ns, rtf->namespaces)
|
|
{
|
|
ResTarget *r = (ResTarget *) lfirst(ns);
|
|
Node *ns_uri;
|
|
|
|
Assert(IsA(r, ResTarget));
|
|
ns_uri = transformExpr(pstate, r->val, EXPR_KIND_FROM_FUNCTION);
|
|
ns_uri = coerce_to_specific_type(pstate, ns_uri,
|
|
TEXTOID, constructName);
|
|
assign_expr_collations(pstate, ns_uri);
|
|
ns_uris = lappend(ns_uris, ns_uri);
|
|
|
|
/* Verify consistency of name list: no dupes, only one DEFAULT */
|
|
if (r->name != NULL)
|
|
{
|
|
foreach(lc2, ns_names)
|
|
{
|
|
Value *ns_node = (Value *) lfirst(lc2);
|
|
|
|
if (ns_node == NULL)
|
|
continue;
|
|
if (strcmp(strVal(ns_node), r->name) == 0)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("namespace name \"%s\" is not unique",
|
|
r->name),
|
|
parser_errposition(pstate, r->location)));
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (default_ns_seen)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("only one default namespace is allowed"),
|
|
parser_errposition(pstate, r->location)));
|
|
default_ns_seen = true;
|
|
}
|
|
|
|
/* We represent DEFAULT by a null pointer */
|
|
ns_names = lappend(ns_names,
|
|
r->name ? makeString(r->name) : NULL);
|
|
}
|
|
|
|
tf->ns_uris = ns_uris;
|
|
tf->ns_names = ns_names;
|
|
}
|
|
|
|
tf->location = rtf->location;
|
|
|
|
pstate->p_lateral_active = false;
|
|
|
|
/*
|
|
* Mark the RTE as LATERAL if the user said LATERAL explicitly, or if
|
|
* there are any lateral cross-references in it.
|
|
*/
|
|
is_lateral = rtf->lateral || contain_vars_of_level((Node *) tf, 0);
|
|
|
|
rte = addRangeTableEntryForTableFunc(pstate,
|
|
tf, rtf->alias, is_lateral, true);
|
|
|
|
return rte;
|
|
}
|
|
|
|
/*
|
|
* transformRangeTableSample --- transform a TABLESAMPLE clause
|
|
*
|
|
* Caller has already transformed rts->relation, we just have to validate
|
|
* the remaining fields and create a TableSampleClause node.
|
|
*/
|
|
static TableSampleClause *
|
|
transformRangeTableSample(ParseState *pstate, RangeTableSample *rts)
|
|
{
|
|
TableSampleClause *tablesample;
|
|
Oid handlerOid;
|
|
Oid funcargtypes[1];
|
|
TsmRoutine *tsm;
|
|
List *fargs;
|
|
ListCell *larg,
|
|
*ltyp;
|
|
|
|
/*
|
|
* To validate the sample method name, look up the handler function, which
|
|
* has the same name, one dummy INTERNAL argument, and a result type of
|
|
* tsm_handler. (Note: tablesample method names are not schema-qualified
|
|
* in the SQL standard; but since they are just functions to us, we allow
|
|
* schema qualification to resolve any potential ambiguity.)
|
|
*/
|
|
funcargtypes[0] = INTERNALOID;
|
|
|
|
handlerOid = LookupFuncName(rts->method, 1, funcargtypes, true);
|
|
|
|
/* we want error to complain about no-such-method, not no-such-function */
|
|
if (!OidIsValid(handlerOid))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_OBJECT),
|
|
errmsg("tablesample method %s does not exist",
|
|
NameListToString(rts->method)),
|
|
parser_errposition(pstate, rts->location)));
|
|
|
|
/* check that handler has correct return type */
|
|
if (get_func_rettype(handlerOid) != TSM_HANDLEROID)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
|
|
errmsg("function %s must return type %s",
|
|
NameListToString(rts->method), "tsm_handler"),
|
|
parser_errposition(pstate, rts->location)));
|
|
|
|
/* OK, run the handler to get TsmRoutine, for argument type info */
|
|
tsm = GetTsmRoutine(handlerOid);
|
|
|
|
tablesample = makeNode(TableSampleClause);
|
|
tablesample->tsmhandler = handlerOid;
|
|
|
|
/* check user provided the expected number of arguments */
|
|
if (list_length(rts->args) != list_length(tsm->parameterTypes))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_TABLESAMPLE_ARGUMENT),
|
|
errmsg_plural("tablesample method %s requires %d argument, not %d",
|
|
"tablesample method %s requires %d arguments, not %d",
|
|
list_length(tsm->parameterTypes),
|
|
NameListToString(rts->method),
|
|
list_length(tsm->parameterTypes),
|
|
list_length(rts->args)),
|
|
parser_errposition(pstate, rts->location)));
|
|
|
|
/*
|
|
* Transform the arguments, typecasting them as needed. Note we must also
|
|
* assign collations now, because assign_query_collations() doesn't
|
|
* examine any substructure of RTEs.
|
|
*/
|
|
fargs = NIL;
|
|
forboth(larg, rts->args, ltyp, tsm->parameterTypes)
|
|
{
|
|
Node *arg = (Node *) lfirst(larg);
|
|
Oid argtype = lfirst_oid(ltyp);
|
|
|
|
arg = transformExpr(pstate, arg, EXPR_KIND_FROM_FUNCTION);
|
|
arg = coerce_to_specific_type(pstate, arg, argtype, "TABLESAMPLE");
|
|
assign_expr_collations(pstate, arg);
|
|
fargs = lappend(fargs, arg);
|
|
}
|
|
tablesample->args = fargs;
|
|
|
|
/* Process REPEATABLE (seed) */
|
|
if (rts->repeatable != NULL)
|
|
{
|
|
Node *arg;
|
|
|
|
if (!tsm->repeatable_across_queries)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("tablesample method %s does not support REPEATABLE",
|
|
NameListToString(rts->method)),
|
|
parser_errposition(pstate, rts->location)));
|
|
|
|
arg = transformExpr(pstate, rts->repeatable, EXPR_KIND_FROM_FUNCTION);
|
|
arg = coerce_to_specific_type(pstate, arg, FLOAT8OID, "REPEATABLE");
|
|
assign_expr_collations(pstate, arg);
|
|
tablesample->repeatable = (Expr *) arg;
|
|
}
|
|
else
|
|
tablesample->repeatable = NULL;
|
|
|
|
return tablesample;
|
|
}
|
|
|
|
/*
|
|
* getRTEForSpecialRelationTypes
|
|
*
|
|
* If given RangeVar refers to a CTE or an EphemeralNamedRelation,
|
|
* build and return an appropriate RTE, otherwise return NULL
|
|
*/
|
|
static RangeTblEntry *
|
|
getRTEForSpecialRelationTypes(ParseState *pstate, RangeVar *rv)
|
|
{
|
|
CommonTableExpr *cte;
|
|
Index levelsup;
|
|
RangeTblEntry *rte;
|
|
|
|
/*
|
|
* if it is a qualified name, it can't be a CTE or tuplestore reference
|
|
*/
|
|
if (rv->schemaname)
|
|
return NULL;
|
|
|
|
cte = scanNameSpaceForCTE(pstate, rv->relname, &levelsup);
|
|
if (cte)
|
|
rte = addRangeTableEntryForCTE(pstate, cte, levelsup, rv, true);
|
|
else if (scanNameSpaceForENR(pstate, rv->relname))
|
|
rte = addRangeTableEntryForENR(pstate, rv, true);
|
|
else
|
|
rte = NULL;
|
|
|
|
return rte;
|
|
}
|
|
|
|
/*
|
|
* transformFromClauseItem -
|
|
* Transform a FROM-clause item, adding any required entries to the
|
|
* range table list being built in the ParseState, and return the
|
|
* transformed item ready to include in the joinlist. Also build a
|
|
* ParseNamespaceItem list describing the names exposed by this item.
|
|
* This routine can recurse to handle SQL92 JOIN expressions.
|
|
*
|
|
* The function return value is the node to add to the jointree (a
|
|
* RangeTblRef or JoinExpr). Additional output parameters are:
|
|
*
|
|
* *top_rte: receives the RTE corresponding to the jointree item.
|
|
* (We could extract this from the function return node, but it saves cycles
|
|
* to pass it back separately.)
|
|
*
|
|
* *top_rti: receives the rangetable index of top_rte. (Ditto.)
|
|
*
|
|
* *namespace: receives a List of ParseNamespaceItems for the RTEs exposed
|
|
* as table/column names by this item. (The lateral_only flags in these items
|
|
* are indeterminate and should be explicitly set by the caller before use.)
|
|
*/
|
|
static Node *
|
|
transformFromClauseItem(ParseState *pstate, Node *n,
|
|
RangeTblEntry **top_rte, int *top_rti,
|
|
List **namespace)
|
|
{
|
|
if (IsA(n, RangeVar))
|
|
{
|
|
/* Plain relation reference, or perhaps a CTE reference */
|
|
RangeVar *rv = (RangeVar *) n;
|
|
RangeTblRef *rtr;
|
|
RangeTblEntry *rte;
|
|
int rtindex;
|
|
|
|
/* Check if it's a CTE or tuplestore reference */
|
|
rte = getRTEForSpecialRelationTypes(pstate, rv);
|
|
|
|
/* if not found above, must be a table reference */
|
|
if (!rte)
|
|
rte = transformTableEntry(pstate, rv);
|
|
|
|
/* assume new rte is at end */
|
|
rtindex = list_length(pstate->p_rtable);
|
|
Assert(rte == rt_fetch(rtindex, pstate->p_rtable));
|
|
*top_rte = rte;
|
|
*top_rti = rtindex;
|
|
*namespace = list_make1(makeDefaultNSItem(rte));
|
|
rtr = makeNode(RangeTblRef);
|
|
rtr->rtindex = rtindex;
|
|
return (Node *) rtr;
|
|
}
|
|
else if (IsA(n, RangeSubselect))
|
|
{
|
|
/* sub-SELECT is like a plain relation */
|
|
RangeTblRef *rtr;
|
|
RangeTblEntry *rte;
|
|
int rtindex;
|
|
|
|
rte = transformRangeSubselect(pstate, (RangeSubselect *) n);
|
|
/* assume new rte is at end */
|
|
rtindex = list_length(pstate->p_rtable);
|
|
Assert(rte == rt_fetch(rtindex, pstate->p_rtable));
|
|
*top_rte = rte;
|
|
*top_rti = rtindex;
|
|
*namespace = list_make1(makeDefaultNSItem(rte));
|
|
rtr = makeNode(RangeTblRef);
|
|
rtr->rtindex = rtindex;
|
|
return (Node *) rtr;
|
|
}
|
|
else if (IsA(n, RangeFunction))
|
|
{
|
|
/* function is like a plain relation */
|
|
RangeTblRef *rtr;
|
|
RangeTblEntry *rte;
|
|
int rtindex;
|
|
|
|
rte = transformRangeFunction(pstate, (RangeFunction *) n);
|
|
/* assume new rte is at end */
|
|
rtindex = list_length(pstate->p_rtable);
|
|
Assert(rte == rt_fetch(rtindex, pstate->p_rtable));
|
|
*top_rte = rte;
|
|
*top_rti = rtindex;
|
|
*namespace = list_make1(makeDefaultNSItem(rte));
|
|
rtr = makeNode(RangeTblRef);
|
|
rtr->rtindex = rtindex;
|
|
return (Node *) rtr;
|
|
}
|
|
else if (IsA(n, RangeTableFunc))
|
|
{
|
|
/* table function is like a plain relation */
|
|
RangeTblRef *rtr;
|
|
RangeTblEntry *rte;
|
|
int rtindex;
|
|
|
|
rte = transformRangeTableFunc(pstate, (RangeTableFunc *) n);
|
|
/* assume new rte is at end */
|
|
rtindex = list_length(pstate->p_rtable);
|
|
Assert(rte == rt_fetch(rtindex, pstate->p_rtable));
|
|
*top_rte = rte;
|
|
*top_rti = rtindex;
|
|
*namespace = list_make1(makeDefaultNSItem(rte));
|
|
rtr = makeNode(RangeTblRef);
|
|
rtr->rtindex = rtindex;
|
|
return (Node *) rtr;
|
|
}
|
|
else if (IsA(n, RangeTableSample))
|
|
{
|
|
/* TABLESAMPLE clause (wrapping some other valid FROM node) */
|
|
RangeTableSample *rts = (RangeTableSample *) n;
|
|
Node *rel;
|
|
RangeTblRef *rtr;
|
|
RangeTblEntry *rte;
|
|
|
|
/* Recursively transform the contained relation */
|
|
rel = transformFromClauseItem(pstate, rts->relation,
|
|
top_rte, top_rti, namespace);
|
|
/* Currently, grammar could only return a RangeVar as contained rel */
|
|
rtr = castNode(RangeTblRef, rel);
|
|
rte = rt_fetch(rtr->rtindex, pstate->p_rtable);
|
|
/* We only support this on plain relations and matviews */
|
|
if (rte->relkind != RELKIND_RELATION &&
|
|
rte->relkind != RELKIND_MATVIEW &&
|
|
rte->relkind != RELKIND_PARTITIONED_TABLE)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("TABLESAMPLE clause can only be applied to tables and materialized views"),
|
|
parser_errposition(pstate, exprLocation(rts->relation))));
|
|
|
|
/* Transform TABLESAMPLE details and attach to the RTE */
|
|
rte->tablesample = transformRangeTableSample(pstate, rts);
|
|
return (Node *) rtr;
|
|
}
|
|
else if (IsA(n, JoinExpr))
|
|
{
|
|
/* A newfangled join expression */
|
|
JoinExpr *j = (JoinExpr *) n;
|
|
RangeTblEntry *l_rte;
|
|
RangeTblEntry *r_rte;
|
|
int l_rtindex;
|
|
int r_rtindex;
|
|
List *l_namespace,
|
|
*r_namespace,
|
|
*my_namespace,
|
|
*l_colnames,
|
|
*r_colnames,
|
|
*res_colnames,
|
|
*l_colvars,
|
|
*r_colvars,
|
|
*res_colvars;
|
|
bool lateral_ok;
|
|
int sv_namespace_length;
|
|
RangeTblEntry *rte;
|
|
int k;
|
|
|
|
/*
|
|
* Recursively process the left subtree, then the right. We must do
|
|
* it in this order for correct visibility of LATERAL references.
|
|
*/
|
|
j->larg = transformFromClauseItem(pstate, j->larg,
|
|
&l_rte,
|
|
&l_rtindex,
|
|
&l_namespace);
|
|
|
|
/*
|
|
* Make the left-side RTEs available for LATERAL access within the
|
|
* right side, by temporarily adding them to the pstate's namespace
|
|
* list. Per SQL:2008, if the join type is not INNER or LEFT then the
|
|
* left-side names must still be exposed, but it's an error to
|
|
* reference them. (Stupid design, but that's what it says.) Hence,
|
|
* we always push them into the namespace, but mark them as not
|
|
* lateral_ok if the jointype is wrong.
|
|
*
|
|
* Notice that we don't require the merged namespace list to be
|
|
* conflict-free. See the comments for scanNameSpaceForRefname().
|
|
*/
|
|
lateral_ok = (j->jointype == JOIN_INNER || j->jointype == JOIN_LEFT);
|
|
setNamespaceLateralState(l_namespace, true, lateral_ok);
|
|
|
|
sv_namespace_length = list_length(pstate->p_namespace);
|
|
pstate->p_namespace = list_concat(pstate->p_namespace, l_namespace);
|
|
|
|
/* And now we can process the RHS */
|
|
j->rarg = transformFromClauseItem(pstate, j->rarg,
|
|
&r_rte,
|
|
&r_rtindex,
|
|
&r_namespace);
|
|
|
|
/* Remove the left-side RTEs from the namespace list again */
|
|
pstate->p_namespace = list_truncate(pstate->p_namespace,
|
|
sv_namespace_length);
|
|
|
|
/*
|
|
* Check for conflicting refnames in left and right subtrees. Must do
|
|
* this because higher levels will assume I hand back a self-
|
|
* consistent namespace list.
|
|
*/
|
|
checkNameSpaceConflicts(pstate, l_namespace, r_namespace);
|
|
|
|
/*
|
|
* Generate combined namespace info for possible use below.
|
|
*/
|
|
my_namespace = list_concat(l_namespace, r_namespace);
|
|
|
|
/*
|
|
* Extract column name and var lists from both subtrees
|
|
*
|
|
* Note: expandRTE returns new lists, safe for me to modify
|
|
*/
|
|
expandRTE(l_rte, l_rtindex, 0, -1, false,
|
|
&l_colnames, &l_colvars);
|
|
expandRTE(r_rte, r_rtindex, 0, -1, false,
|
|
&r_colnames, &r_colvars);
|
|
|
|
/*
|
|
* Natural join does not explicitly specify columns; must generate
|
|
* columns to join. Need to run through the list of columns from each
|
|
* table or join result and match up the column names. Use the first
|
|
* table, and check every column in the second table for a match.
|
|
* (We'll check that the matches were unique later on.) The result of
|
|
* this step is a list of column names just like an explicitly-written
|
|
* USING list.
|
|
*/
|
|
if (j->isNatural)
|
|
{
|
|
List *rlist = NIL;
|
|
ListCell *lx,
|
|
*rx;
|
|
|
|
Assert(j->usingClause == NIL); /* shouldn't have USING() too */
|
|
|
|
foreach(lx, l_colnames)
|
|
{
|
|
char *l_colname = strVal(lfirst(lx));
|
|
Value *m_name = NULL;
|
|
|
|
foreach(rx, r_colnames)
|
|
{
|
|
char *r_colname = strVal(lfirst(rx));
|
|
|
|
if (strcmp(l_colname, r_colname) == 0)
|
|
{
|
|
m_name = makeString(l_colname);
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* matched a right column? then keep as join column... */
|
|
if (m_name != NULL)
|
|
rlist = lappend(rlist, m_name);
|
|
}
|
|
|
|
j->usingClause = rlist;
|
|
}
|
|
|
|
/*
|
|
* Now transform the join qualifications, if any.
|
|
*/
|
|
res_colnames = NIL;
|
|
res_colvars = NIL;
|
|
|
|
if (j->usingClause)
|
|
{
|
|
/*
|
|
* JOIN/USING (or NATURAL JOIN, as transformed above). Transform
|
|
* the list into an explicit ON-condition, and generate a list of
|
|
* merged result columns.
|
|
*/
|
|
List *ucols = j->usingClause;
|
|
List *l_usingvars = NIL;
|
|
List *r_usingvars = NIL;
|
|
ListCell *ucol;
|
|
|
|
Assert(j->quals == NULL); /* shouldn't have ON() too */
|
|
|
|
foreach(ucol, ucols)
|
|
{
|
|
char *u_colname = strVal(lfirst(ucol));
|
|
ListCell *col;
|
|
int ndx;
|
|
int l_index = -1;
|
|
int r_index = -1;
|
|
Var *l_colvar,
|
|
*r_colvar;
|
|
|
|
/* Check for USING(foo,foo) */
|
|
foreach(col, res_colnames)
|
|
{
|
|
char *res_colname = strVal(lfirst(col));
|
|
|
|
if (strcmp(res_colname, u_colname) == 0)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_DUPLICATE_COLUMN),
|
|
errmsg("column name \"%s\" appears more than once in USING clause",
|
|
u_colname)));
|
|
}
|
|
|
|
/* Find it in left input */
|
|
ndx = 0;
|
|
foreach(col, l_colnames)
|
|
{
|
|
char *l_colname = strVal(lfirst(col));
|
|
|
|
if (strcmp(l_colname, u_colname) == 0)
|
|
{
|
|
if (l_index >= 0)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_AMBIGUOUS_COLUMN),
|
|
errmsg("common column name \"%s\" appears more than once in left table",
|
|
u_colname)));
|
|
l_index = ndx;
|
|
}
|
|
ndx++;
|
|
}
|
|
if (l_index < 0)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_COLUMN),
|
|
errmsg("column \"%s\" specified in USING clause does not exist in left table",
|
|
u_colname)));
|
|
|
|
/* Find it in right input */
|
|
ndx = 0;
|
|
foreach(col, r_colnames)
|
|
{
|
|
char *r_colname = strVal(lfirst(col));
|
|
|
|
if (strcmp(r_colname, u_colname) == 0)
|
|
{
|
|
if (r_index >= 0)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_AMBIGUOUS_COLUMN),
|
|
errmsg("common column name \"%s\" appears more than once in right table",
|
|
u_colname)));
|
|
r_index = ndx;
|
|
}
|
|
ndx++;
|
|
}
|
|
if (r_index < 0)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_COLUMN),
|
|
errmsg("column \"%s\" specified in USING clause does not exist in right table",
|
|
u_colname)));
|
|
|
|
l_colvar = list_nth(l_colvars, l_index);
|
|
l_usingvars = lappend(l_usingvars, l_colvar);
|
|
r_colvar = list_nth(r_colvars, r_index);
|
|
r_usingvars = lappend(r_usingvars, r_colvar);
|
|
|
|
res_colnames = lappend(res_colnames, lfirst(ucol));
|
|
res_colvars = lappend(res_colvars,
|
|
buildMergedJoinVar(pstate,
|
|
j->jointype,
|
|
l_colvar,
|
|
r_colvar));
|
|
}
|
|
|
|
j->quals = transformJoinUsingClause(pstate,
|
|
l_rte,
|
|
r_rte,
|
|
l_usingvars,
|
|
r_usingvars);
|
|
}
|
|
else if (j->quals)
|
|
{
|
|
/* User-written ON-condition; transform it */
|
|
j->quals = transformJoinOnClause(pstate, j, my_namespace);
|
|
}
|
|
else
|
|
{
|
|
/* CROSS JOIN: no quals */
|
|
}
|
|
|
|
/* Add remaining columns from each side to the output columns */
|
|
extractRemainingColumns(res_colnames,
|
|
l_colnames, l_colvars,
|
|
&l_colnames, &l_colvars);
|
|
extractRemainingColumns(res_colnames,
|
|
r_colnames, r_colvars,
|
|
&r_colnames, &r_colvars);
|
|
res_colnames = list_concat(res_colnames, l_colnames);
|
|
res_colvars = list_concat(res_colvars, l_colvars);
|
|
res_colnames = list_concat(res_colnames, r_colnames);
|
|
res_colvars = list_concat(res_colvars, r_colvars);
|
|
|
|
/*
|
|
* Check alias (AS clause), if any.
|
|
*/
|
|
if (j->alias)
|
|
{
|
|
if (j->alias->colnames != NIL)
|
|
{
|
|
if (list_length(j->alias->colnames) > list_length(res_colnames))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("column alias list for \"%s\" has too many entries",
|
|
j->alias->aliasname)));
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Now build an RTE for the result of the join
|
|
*/
|
|
rte = addRangeTableEntryForJoin(pstate,
|
|
res_colnames,
|
|
j->jointype,
|
|
res_colvars,
|
|
j->alias,
|
|
true);
|
|
|
|
/* assume new rte is at end */
|
|
j->rtindex = list_length(pstate->p_rtable);
|
|
Assert(rte == rt_fetch(j->rtindex, pstate->p_rtable));
|
|
|
|
*top_rte = rte;
|
|
*top_rti = j->rtindex;
|
|
|
|
/* make a matching link to the JoinExpr for later use */
|
|
for (k = list_length(pstate->p_joinexprs) + 1; k < j->rtindex; k++)
|
|
pstate->p_joinexprs = lappend(pstate->p_joinexprs, NULL);
|
|
pstate->p_joinexprs = lappend(pstate->p_joinexprs, j);
|
|
Assert(list_length(pstate->p_joinexprs) == j->rtindex);
|
|
|
|
/*
|
|
* Prepare returned namespace list. If the JOIN has an alias then it
|
|
* hides the contained RTEs completely; otherwise, the contained RTEs
|
|
* are still visible as table names, but are not visible for
|
|
* unqualified column-name access.
|
|
*
|
|
* Note: if there are nested alias-less JOINs, the lower-level ones
|
|
* will remain in the list although they have neither p_rel_visible
|
|
* nor p_cols_visible set. We could delete such list items, but it's
|
|
* unclear that it's worth expending cycles to do so.
|
|
*/
|
|
if (j->alias != NULL)
|
|
my_namespace = NIL;
|
|
else
|
|
setNamespaceColumnVisibility(my_namespace, false);
|
|
|
|
/*
|
|
* The join RTE itself is always made visible for unqualified column
|
|
* names. It's visible as a relation name only if it has an alias.
|
|
*/
|
|
*namespace = lappend(my_namespace,
|
|
makeNamespaceItem(rte,
|
|
(j->alias != NULL),
|
|
true,
|
|
false,
|
|
true));
|
|
|
|
return (Node *) j;
|
|
}
|
|
else
|
|
elog(ERROR, "unrecognized node type: %d", (int) nodeTag(n));
|
|
return NULL; /* can't get here, keep compiler quiet */
|
|
}
|
|
|
|
/*
|
|
* buildMergedJoinVar -
|
|
* generate a suitable replacement expression for a merged join column
|
|
*/
|
|
static Node *
|
|
buildMergedJoinVar(ParseState *pstate, JoinType jointype,
|
|
Var *l_colvar, Var *r_colvar)
|
|
{
|
|
Oid outcoltype;
|
|
int32 outcoltypmod;
|
|
Node *l_node,
|
|
*r_node,
|
|
*res_node;
|
|
|
|
/*
|
|
* Choose output type if input types are dissimilar.
|
|
*/
|
|
outcoltype = l_colvar->vartype;
|
|
outcoltypmod = l_colvar->vartypmod;
|
|
if (outcoltype != r_colvar->vartype)
|
|
{
|
|
outcoltype = select_common_type(pstate,
|
|
list_make2(l_colvar, r_colvar),
|
|
"JOIN/USING",
|
|
NULL);
|
|
outcoltypmod = -1; /* ie, unknown */
|
|
}
|
|
else if (outcoltypmod != r_colvar->vartypmod)
|
|
{
|
|
/* same type, but not same typmod */
|
|
outcoltypmod = -1; /* ie, unknown */
|
|
}
|
|
|
|
/*
|
|
* Insert coercion functions if needed. Note that a difference in typmod
|
|
* can only happen if input has typmod but outcoltypmod is -1. In that
|
|
* case we insert a RelabelType to clearly mark that result's typmod is
|
|
* not same as input. We never need coerce_type_typmod.
|
|
*/
|
|
if (l_colvar->vartype != outcoltype)
|
|
l_node = coerce_type(pstate, (Node *) l_colvar, l_colvar->vartype,
|
|
outcoltype, outcoltypmod,
|
|
COERCION_IMPLICIT, COERCE_IMPLICIT_CAST, -1);
|
|
else if (l_colvar->vartypmod != outcoltypmod)
|
|
l_node = (Node *) makeRelabelType((Expr *) l_colvar,
|
|
outcoltype, outcoltypmod,
|
|
InvalidOid, /* fixed below */
|
|
COERCE_IMPLICIT_CAST);
|
|
else
|
|
l_node = (Node *) l_colvar;
|
|
|
|
if (r_colvar->vartype != outcoltype)
|
|
r_node = coerce_type(pstate, (Node *) r_colvar, r_colvar->vartype,
|
|
outcoltype, outcoltypmod,
|
|
COERCION_IMPLICIT, COERCE_IMPLICIT_CAST, -1);
|
|
else if (r_colvar->vartypmod != outcoltypmod)
|
|
r_node = (Node *) makeRelabelType((Expr *) r_colvar,
|
|
outcoltype, outcoltypmod,
|
|
InvalidOid, /* fixed below */
|
|
COERCE_IMPLICIT_CAST);
|
|
else
|
|
r_node = (Node *) r_colvar;
|
|
|
|
/*
|
|
* Choose what to emit
|
|
*/
|
|
switch (jointype)
|
|
{
|
|
case JOIN_INNER:
|
|
|
|
/*
|
|
* We can use either var; prefer non-coerced one if available.
|
|
*/
|
|
if (IsA(l_node, Var))
|
|
res_node = l_node;
|
|
else if (IsA(r_node, Var))
|
|
res_node = r_node;
|
|
else
|
|
res_node = l_node;
|
|
break;
|
|
case JOIN_LEFT:
|
|
/* Always use left var */
|
|
res_node = l_node;
|
|
break;
|
|
case JOIN_RIGHT:
|
|
/* Always use right var */
|
|
res_node = r_node;
|
|
break;
|
|
case JOIN_FULL:
|
|
{
|
|
/*
|
|
* Here we must build a COALESCE expression to ensure that the
|
|
* join output is non-null if either input is.
|
|
*/
|
|
CoalesceExpr *c = makeNode(CoalesceExpr);
|
|
|
|
c->coalescetype = outcoltype;
|
|
/* coalescecollid will get set below */
|
|
c->args = list_make2(l_node, r_node);
|
|
c->location = -1;
|
|
res_node = (Node *) c;
|
|
break;
|
|
}
|
|
default:
|
|
elog(ERROR, "unrecognized join type: %d", (int) jointype);
|
|
res_node = NULL; /* keep compiler quiet */
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Apply assign_expr_collations to fix up the collation info in the
|
|
* coercion and CoalesceExpr nodes, if we made any. This must be done now
|
|
* so that the join node's alias vars show correct collation info.
|
|
*/
|
|
assign_expr_collations(pstate, res_node);
|
|
|
|
return res_node;
|
|
}
|
|
|
|
/*
|
|
* makeNamespaceItem -
|
|
* Convenience subroutine to construct a ParseNamespaceItem.
|
|
*/
|
|
static ParseNamespaceItem *
|
|
makeNamespaceItem(RangeTblEntry *rte, bool rel_visible, bool cols_visible,
|
|
bool lateral_only, bool lateral_ok)
|
|
{
|
|
ParseNamespaceItem *nsitem;
|
|
|
|
nsitem = (ParseNamespaceItem *) palloc(sizeof(ParseNamespaceItem));
|
|
nsitem->p_rte = rte;
|
|
nsitem->p_rel_visible = rel_visible;
|
|
nsitem->p_cols_visible = cols_visible;
|
|
nsitem->p_lateral_only = lateral_only;
|
|
nsitem->p_lateral_ok = lateral_ok;
|
|
return nsitem;
|
|
}
|
|
|
|
/*
|
|
* setNamespaceColumnVisibility -
|
|
* Convenience subroutine to update cols_visible flags in a namespace list.
|
|
*/
|
|
static void
|
|
setNamespaceColumnVisibility(List *namespace, bool cols_visible)
|
|
{
|
|
ListCell *lc;
|
|
|
|
foreach(lc, namespace)
|
|
{
|
|
ParseNamespaceItem *nsitem = (ParseNamespaceItem *) lfirst(lc);
|
|
|
|
nsitem->p_cols_visible = cols_visible;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* setNamespaceLateralState -
|
|
* Convenience subroutine to update LATERAL flags in a namespace list.
|
|
*/
|
|
static void
|
|
setNamespaceLateralState(List *namespace, bool lateral_only, bool lateral_ok)
|
|
{
|
|
ListCell *lc;
|
|
|
|
foreach(lc, namespace)
|
|
{
|
|
ParseNamespaceItem *nsitem = (ParseNamespaceItem *) lfirst(lc);
|
|
|
|
nsitem->p_lateral_only = lateral_only;
|
|
nsitem->p_lateral_ok = lateral_ok;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* transformWhereClause -
|
|
* Transform the qualification and make sure it is of type boolean.
|
|
* Used for WHERE and allied clauses.
|
|
*
|
|
* constructName does not affect the semantics, but is used in error messages
|
|
*/
|
|
Node *
|
|
transformWhereClause(ParseState *pstate, Node *clause,
|
|
ParseExprKind exprKind, const char *constructName)
|
|
{
|
|
Node *qual;
|
|
|
|
if (clause == NULL)
|
|
return NULL;
|
|
|
|
qual = transformExpr(pstate, clause, exprKind);
|
|
|
|
qual = coerce_to_boolean(pstate, qual, constructName);
|
|
|
|
return qual;
|
|
}
|
|
|
|
|
|
/*
|
|
* transformLimitClause -
|
|
* Transform the expression and make sure it is of type bigint.
|
|
* Used for LIMIT and allied clauses.
|
|
*
|
|
* Note: as of Postgres 8.2, LIMIT expressions are expected to yield int8,
|
|
* rather than int4 as before.
|
|
*
|
|
* constructName does not affect the semantics, but is used in error messages
|
|
*/
|
|
Node *
|
|
transformLimitClause(ParseState *pstate, Node *clause,
|
|
ParseExprKind exprKind, const char *constructName)
|
|
{
|
|
Node *qual;
|
|
|
|
if (clause == NULL)
|
|
return NULL;
|
|
|
|
qual = transformExpr(pstate, clause, exprKind);
|
|
|
|
qual = coerce_to_specific_type(pstate, qual, INT8OID, constructName);
|
|
|
|
/* LIMIT can't refer to any variables of the current query */
|
|
checkExprIsVarFree(pstate, qual, constructName);
|
|
|
|
return qual;
|
|
}
|
|
|
|
/*
|
|
* checkExprIsVarFree
|
|
* Check that given expr has no Vars of the current query level
|
|
* (aggregates and window functions should have been rejected already).
|
|
*
|
|
* This is used to check expressions that have to have a consistent value
|
|
* across all rows of the query, such as a LIMIT. Arguably it should reject
|
|
* volatile functions, too, but we don't do that --- whatever value the
|
|
* function gives on first execution is what you get.
|
|
*
|
|
* constructName does not affect the semantics, but is used in error messages
|
|
*/
|
|
static void
|
|
checkExprIsVarFree(ParseState *pstate, Node *n, const char *constructName)
|
|
{
|
|
if (contain_vars_of_level(n, 0))
|
|
{
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
|
|
/* translator: %s is name of a SQL construct, eg LIMIT */
|
|
errmsg("argument of %s must not contain variables",
|
|
constructName),
|
|
parser_errposition(pstate,
|
|
locate_var_of_level(n, 0))));
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* checkTargetlistEntrySQL92 -
|
|
* Validate a targetlist entry found by findTargetlistEntrySQL92
|
|
*
|
|
* When we select a pre-existing tlist entry as a result of syntax such
|
|
* as "GROUP BY 1", we have to make sure it is acceptable for use in the
|
|
* indicated clause type; transformExpr() will have treated it as a regular
|
|
* targetlist item.
|
|
*/
|
|
static void
|
|
checkTargetlistEntrySQL92(ParseState *pstate, TargetEntry *tle,
|
|
ParseExprKind exprKind)
|
|
{
|
|
switch (exprKind)
|
|
{
|
|
case EXPR_KIND_GROUP_BY:
|
|
/* reject aggregates and window functions */
|
|
if (pstate->p_hasAggs &&
|
|
contain_aggs_of_level((Node *) tle->expr, 0))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_GROUPING_ERROR),
|
|
/* translator: %s is name of a SQL construct, eg GROUP BY */
|
|
errmsg("aggregate functions are not allowed in %s",
|
|
ParseExprKindName(exprKind)),
|
|
parser_errposition(pstate,
|
|
locate_agg_of_level((Node *) tle->expr, 0))));
|
|
if (pstate->p_hasWindowFuncs &&
|
|
contain_windowfuncs((Node *) tle->expr))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WINDOWING_ERROR),
|
|
/* translator: %s is name of a SQL construct, eg GROUP BY */
|
|
errmsg("window functions are not allowed in %s",
|
|
ParseExprKindName(exprKind)),
|
|
parser_errposition(pstate,
|
|
locate_windowfunc((Node *) tle->expr))));
|
|
break;
|
|
case EXPR_KIND_ORDER_BY:
|
|
/* no extra checks needed */
|
|
break;
|
|
case EXPR_KIND_DISTINCT_ON:
|
|
/* no extra checks needed */
|
|
break;
|
|
default:
|
|
elog(ERROR, "unexpected exprKind in checkTargetlistEntrySQL92");
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* findTargetlistEntrySQL92 -
|
|
* Returns the targetlist entry matching the given (untransformed) node.
|
|
* If no matching entry exists, one is created and appended to the target
|
|
* list as a "resjunk" node.
|
|
*
|
|
* This function supports the old SQL92 ORDER BY interpretation, where the
|
|
* expression is an output column name or number. If we fail to find a
|
|
* match of that sort, we fall through to the SQL99 rules. For historical
|
|
* reasons, Postgres also allows this interpretation for GROUP BY, though
|
|
* the standard never did. However, for GROUP BY we prefer a SQL99 match.
|
|
* This function is *not* used for WINDOW definitions.
|
|
*
|
|
* node the ORDER BY, GROUP BY, or DISTINCT ON expression to be matched
|
|
* tlist the target list (passed by reference so we can append to it)
|
|
* exprKind identifies clause type being processed
|
|
*/
|
|
static TargetEntry *
|
|
findTargetlistEntrySQL92(ParseState *pstate, Node *node, List **tlist,
|
|
ParseExprKind exprKind)
|
|
{
|
|
ListCell *tl;
|
|
|
|
/*----------
|
|
* Handle two special cases as mandated by the SQL92 spec:
|
|
*
|
|
* 1. Bare ColumnName (no qualifier or subscripts)
|
|
* For a bare identifier, we search for a matching column name
|
|
* in the existing target list. Multiple matches are an error
|
|
* unless they refer to identical values; for example,
|
|
* we allow SELECT a, a FROM table ORDER BY a
|
|
* but not SELECT a AS b, b FROM table ORDER BY b
|
|
* If no match is found, we fall through and treat the identifier
|
|
* as an expression.
|
|
* For GROUP BY, it is incorrect to match the grouping item against
|
|
* targetlist entries: according to SQL92, an identifier in GROUP BY
|
|
* is a reference to a column name exposed by FROM, not to a target
|
|
* list column. However, many implementations (including pre-7.0
|
|
* PostgreSQL) accept this anyway. So for GROUP BY, we look first
|
|
* to see if the identifier matches any FROM column name, and only
|
|
* try for a targetlist name if it doesn't. This ensures that we
|
|
* adhere to the spec in the case where the name could be both.
|
|
* DISTINCT ON isn't in the standard, so we can do what we like there;
|
|
* we choose to make it work like ORDER BY, on the rather flimsy
|
|
* grounds that ordinary DISTINCT works on targetlist entries.
|
|
*
|
|
* 2. IntegerConstant
|
|
* This means to use the n'th item in the existing target list.
|
|
* Note that it would make no sense to order/group/distinct by an
|
|
* actual constant, so this does not create a conflict with SQL99.
|
|
* GROUP BY column-number is not allowed by SQL92, but since
|
|
* the standard has no other behavior defined for this syntax,
|
|
* we may as well accept this common extension.
|
|
*
|
|
* Note that pre-existing resjunk targets must not be used in either case,
|
|
* since the user didn't write them in his SELECT list.
|
|
*
|
|
* If neither special case applies, fall through to treat the item as
|
|
* an expression per SQL99.
|
|
*----------
|
|
*/
|
|
if (IsA(node, ColumnRef) &&
|
|
list_length(((ColumnRef *) node)->fields) == 1 &&
|
|
IsA(linitial(((ColumnRef *) node)->fields), String))
|
|
{
|
|
char *name = strVal(linitial(((ColumnRef *) node)->fields));
|
|
int location = ((ColumnRef *) node)->location;
|
|
|
|
if (exprKind == EXPR_KIND_GROUP_BY)
|
|
{
|
|
/*
|
|
* In GROUP BY, we must prefer a match against a FROM-clause
|
|
* column to one against the targetlist. Look to see if there is
|
|
* a matching column. If so, fall through to use SQL99 rules.
|
|
* NOTE: if name could refer ambiguously to more than one column
|
|
* name exposed by FROM, colNameToVar will ereport(ERROR). That's
|
|
* just what we want here.
|
|
*
|
|
* Small tweak for 7.4.3: ignore matches in upper query levels.
|
|
* This effectively changes the search order for bare names to (1)
|
|
* local FROM variables, (2) local targetlist aliases, (3) outer
|
|
* FROM variables, whereas before it was (1) (3) (2). SQL92 and
|
|
* SQL99 do not allow GROUPing BY an outer reference, so this
|
|
* breaks no cases that are legal per spec, and it seems a more
|
|
* self-consistent behavior.
|
|
*/
|
|
if (colNameToVar(pstate, name, true, location) != NULL)
|
|
name = NULL;
|
|
}
|
|
|
|
if (name != NULL)
|
|
{
|
|
TargetEntry *target_result = NULL;
|
|
|
|
foreach(tl, *tlist)
|
|
{
|
|
TargetEntry *tle = (TargetEntry *) lfirst(tl);
|
|
|
|
if (!tle->resjunk &&
|
|
strcmp(tle->resname, name) == 0)
|
|
{
|
|
if (target_result != NULL)
|
|
{
|
|
if (!equal(target_result->expr, tle->expr))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_AMBIGUOUS_COLUMN),
|
|
|
|
/*------
|
|
translator: first %s is name of a SQL construct, eg ORDER BY */
|
|
errmsg("%s \"%s\" is ambiguous",
|
|
ParseExprKindName(exprKind),
|
|
name),
|
|
parser_errposition(pstate, location)));
|
|
}
|
|
else
|
|
target_result = tle;
|
|
/* Stay in loop to check for ambiguity */
|
|
}
|
|
}
|
|
if (target_result != NULL)
|
|
{
|
|
/* return the first match, after suitable validation */
|
|
checkTargetlistEntrySQL92(pstate, target_result, exprKind);
|
|
return target_result;
|
|
}
|
|
}
|
|
}
|
|
if (IsA(node, A_Const))
|
|
{
|
|
Value *val = &((A_Const *) node)->val;
|
|
int location = ((A_Const *) node)->location;
|
|
int targetlist_pos = 0;
|
|
int target_pos;
|
|
|
|
if (!IsA(val, Integer))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
/* translator: %s is name of a SQL construct, eg ORDER BY */
|
|
errmsg("non-integer constant in %s",
|
|
ParseExprKindName(exprKind)),
|
|
parser_errposition(pstate, location)));
|
|
|
|
target_pos = intVal(val);
|
|
foreach(tl, *tlist)
|
|
{
|
|
TargetEntry *tle = (TargetEntry *) lfirst(tl);
|
|
|
|
if (!tle->resjunk)
|
|
{
|
|
if (++targetlist_pos == target_pos)
|
|
{
|
|
/* return the unique match, after suitable validation */
|
|
checkTargetlistEntrySQL92(pstate, tle, exprKind);
|
|
return tle;
|
|
}
|
|
}
|
|
}
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
|
|
/* translator: %s is name of a SQL construct, eg ORDER BY */
|
|
errmsg("%s position %d is not in select list",
|
|
ParseExprKindName(exprKind), target_pos),
|
|
parser_errposition(pstate, location)));
|
|
}
|
|
|
|
/*
|
|
* Otherwise, we have an expression, so process it per SQL99 rules.
|
|
*/
|
|
return findTargetlistEntrySQL99(pstate, node, tlist, exprKind);
|
|
}
|
|
|
|
/*
|
|
* findTargetlistEntrySQL99 -
|
|
* Returns the targetlist entry matching the given (untransformed) node.
|
|
* If no matching entry exists, one is created and appended to the target
|
|
* list as a "resjunk" node.
|
|
*
|
|
* This function supports the SQL99 interpretation, wherein the expression
|
|
* is just an ordinary expression referencing input column names.
|
|
*
|
|
* node the ORDER BY, GROUP BY, etc expression to be matched
|
|
* tlist the target list (passed by reference so we can append to it)
|
|
* exprKind identifies clause type being processed
|
|
*/
|
|
static TargetEntry *
|
|
findTargetlistEntrySQL99(ParseState *pstate, Node *node, List **tlist,
|
|
ParseExprKind exprKind)
|
|
{
|
|
TargetEntry *target_result;
|
|
ListCell *tl;
|
|
Node *expr;
|
|
|
|
/*
|
|
* Convert the untransformed node to a transformed expression, and search
|
|
* for a match in the tlist. NOTE: it doesn't really matter whether there
|
|
* is more than one match. Also, we are willing to match an existing
|
|
* resjunk target here, though the SQL92 cases above must ignore resjunk
|
|
* targets.
|
|
*/
|
|
expr = transformExpr(pstate, node, exprKind);
|
|
|
|
foreach(tl, *tlist)
|
|
{
|
|
TargetEntry *tle = (TargetEntry *) lfirst(tl);
|
|
Node *texpr;
|
|
|
|
/*
|
|
* Ignore any implicit cast on the existing tlist expression.
|
|
*
|
|
* This essentially allows the ORDER/GROUP/etc item to adopt the same
|
|
* datatype previously selected for a textually-equivalent tlist item.
|
|
* There can't be any implicit cast at top level in an ordinary SELECT
|
|
* tlist at this stage, but the case does arise with ORDER BY in an
|
|
* aggregate function.
|
|
*/
|
|
texpr = strip_implicit_coercions((Node *) tle->expr);
|
|
|
|
if (equal(expr, texpr))
|
|
return tle;
|
|
}
|
|
|
|
/*
|
|
* If no matches, construct a new target entry which is appended to the
|
|
* end of the target list. This target is given resjunk = true so that it
|
|
* will not be projected into the final tuple.
|
|
*/
|
|
target_result = transformTargetEntry(pstate, node, expr, exprKind,
|
|
NULL, true);
|
|
|
|
*tlist = lappend(*tlist, target_result);
|
|
|
|
return target_result;
|
|
}
|
|
|
|
/*-------------------------------------------------------------------------
|
|
* Flatten out parenthesized sublists in grouping lists, and some cases
|
|
* of nested grouping sets.
|
|
*
|
|
* Inside a grouping set (ROLLUP, CUBE, or GROUPING SETS), we expect the
|
|
* content to be nested no more than 2 deep: i.e. ROLLUP((a,b),(c,d)) is
|
|
* ok, but ROLLUP((a,(b,c)),d) is flattened to ((a,b,c),d), which we then
|
|
* (later) normalize to ((a,b,c),(d)).
|
|
*
|
|
* CUBE or ROLLUP can be nested inside GROUPING SETS (but not the reverse),
|
|
* and we leave that alone if we find it. But if we see GROUPING SETS inside
|
|
* GROUPING SETS, we can flatten and normalize as follows:
|
|
* GROUPING SETS (a, (b,c), GROUPING SETS ((c,d),(e)), (f,g))
|
|
* becomes
|
|
* GROUPING SETS ((a), (b,c), (c,d), (e), (f,g))
|
|
*
|
|
* This is per the spec's syntax transformations, but these are the only such
|
|
* transformations we do in parse analysis, so that queries retain the
|
|
* originally specified grouping set syntax for CUBE and ROLLUP as much as
|
|
* possible when deparsed. (Full expansion of the result into a list of
|
|
* grouping sets is left to the planner.)
|
|
*
|
|
* When we're done, the resulting list should contain only these possible
|
|
* elements:
|
|
* - an expression
|
|
* - a CUBE or ROLLUP with a list of expressions nested 2 deep
|
|
* - a GROUPING SET containing any of:
|
|
* - expression lists
|
|
* - empty grouping sets
|
|
* - CUBE or ROLLUP nodes with lists nested 2 deep
|
|
* The return is a new list, but doesn't deep-copy the old nodes except for
|
|
* GroupingSet nodes.
|
|
*
|
|
* As a side effect, flag whether the list has any GroupingSet nodes.
|
|
*-------------------------------------------------------------------------
|
|
*/
|
|
static Node *
|
|
flatten_grouping_sets(Node *expr, bool toplevel, bool *hasGroupingSets)
|
|
{
|
|
/* just in case of pathological input */
|
|
check_stack_depth();
|
|
|
|
if (expr == (Node *) NIL)
|
|
return (Node *) NIL;
|
|
|
|
switch (expr->type)
|
|
{
|
|
case T_RowExpr:
|
|
{
|
|
RowExpr *r = (RowExpr *) expr;
|
|
|
|
if (r->row_format == COERCE_IMPLICIT_CAST)
|
|
return flatten_grouping_sets((Node *) r->args,
|
|
false, NULL);
|
|
}
|
|
break;
|
|
case T_GroupingSet:
|
|
{
|
|
GroupingSet *gset = (GroupingSet *) expr;
|
|
ListCell *l2;
|
|
List *result_set = NIL;
|
|
|
|
if (hasGroupingSets)
|
|
*hasGroupingSets = true;
|
|
|
|
/*
|
|
* at the top level, we skip over all empty grouping sets; the
|
|
* caller can supply the canonical GROUP BY () if nothing is
|
|
* left.
|
|
*/
|
|
|
|
if (toplevel && gset->kind == GROUPING_SET_EMPTY)
|
|
return (Node *) NIL;
|
|
|
|
foreach(l2, gset->content)
|
|
{
|
|
Node *n1 = lfirst(l2);
|
|
Node *n2 = flatten_grouping_sets(n1, false, NULL);
|
|
|
|
if (IsA(n1, GroupingSet) &&
|
|
((GroupingSet *) n1)->kind == GROUPING_SET_SETS)
|
|
result_set = list_concat(result_set, (List *) n2);
|
|
else
|
|
result_set = lappend(result_set, n2);
|
|
}
|
|
|
|
/*
|
|
* At top level, keep the grouping set node; but if we're in a
|
|
* nested grouping set, then we need to concat the flattened
|
|
* result into the outer list if it's simply nested.
|
|
*/
|
|
|
|
if (toplevel || (gset->kind != GROUPING_SET_SETS))
|
|
{
|
|
return (Node *) makeGroupingSet(gset->kind, result_set, gset->location);
|
|
}
|
|
else
|
|
return (Node *) result_set;
|
|
}
|
|
case T_List:
|
|
{
|
|
List *result = NIL;
|
|
ListCell *l;
|
|
|
|
foreach(l, (List *) expr)
|
|
{
|
|
Node *n = flatten_grouping_sets(lfirst(l), toplevel, hasGroupingSets);
|
|
|
|
if (n != (Node *) NIL)
|
|
{
|
|
if (IsA(n, List))
|
|
result = list_concat(result, (List *) n);
|
|
else
|
|
result = lappend(result, n);
|
|
}
|
|
}
|
|
|
|
return (Node *) result;
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
|
|
return expr;
|
|
}
|
|
|
|
/*
|
|
* Transform a single expression within a GROUP BY clause or grouping set.
|
|
*
|
|
* The expression is added to the targetlist if not already present, and to the
|
|
* flatresult list (which will become the groupClause) if not already present
|
|
* there. The sortClause is consulted for operator and sort order hints.
|
|
*
|
|
* Returns the ressortgroupref of the expression.
|
|
*
|
|
* flatresult reference to flat list of SortGroupClause nodes
|
|
* seen_local bitmapset of sortgrouprefs already seen at the local level
|
|
* pstate ParseState
|
|
* gexpr node to transform
|
|
* targetlist reference to TargetEntry list
|
|
* sortClause ORDER BY clause (SortGroupClause nodes)
|
|
* exprKind expression kind
|
|
* useSQL99 SQL99 rather than SQL92 syntax
|
|
* toplevel false if within any grouping set
|
|
*/
|
|
static Index
|
|
transformGroupClauseExpr(List **flatresult, Bitmapset *seen_local,
|
|
ParseState *pstate, Node *gexpr,
|
|
List **targetlist, List *sortClause,
|
|
ParseExprKind exprKind, bool useSQL99, bool toplevel)
|
|
{
|
|
TargetEntry *tle;
|
|
bool found = false;
|
|
|
|
if (useSQL99)
|
|
tle = findTargetlistEntrySQL99(pstate, gexpr,
|
|
targetlist, exprKind);
|
|
else
|
|
tle = findTargetlistEntrySQL92(pstate, gexpr,
|
|
targetlist, exprKind);
|
|
|
|
if (tle->ressortgroupref > 0)
|
|
{
|
|
ListCell *sl;
|
|
|
|
/*
|
|
* Eliminate duplicates (GROUP BY x, x) but only at local level.
|
|
* (Duplicates in grouping sets can affect the number of returned
|
|
* rows, so can't be dropped indiscriminately.)
|
|
*
|
|
* Since we don't care about anything except the sortgroupref, we can
|
|
* use a bitmapset rather than scanning lists.
|
|
*/
|
|
if (bms_is_member(tle->ressortgroupref, seen_local))
|
|
return 0;
|
|
|
|
/*
|
|
* If we're already in the flat clause list, we don't need to consider
|
|
* adding ourselves again.
|
|
*/
|
|
found = targetIsInSortList(tle, InvalidOid, *flatresult);
|
|
if (found)
|
|
return tle->ressortgroupref;
|
|
|
|
/*
|
|
* If the GROUP BY tlist entry also appears in ORDER BY, copy operator
|
|
* info from the (first) matching ORDER BY item. This means that if
|
|
* you write something like "GROUP BY foo ORDER BY foo USING <<<", the
|
|
* GROUP BY operation silently takes on the equality semantics implied
|
|
* by the ORDER BY. There are two reasons to do this: it improves the
|
|
* odds that we can implement both GROUP BY and ORDER BY with a single
|
|
* sort step, and it allows the user to choose the equality semantics
|
|
* used by GROUP BY, should she be working with a datatype that has
|
|
* more than one equality operator.
|
|
*
|
|
* If we're in a grouping set, though, we force our requested ordering
|
|
* to be NULLS LAST, because if we have any hope of using a sorted agg
|
|
* for the job, we're going to be tacking on generated NULL values
|
|
* after the corresponding groups. If the user demands nulls first,
|
|
* another sort step is going to be inevitable, but that's the
|
|
* planner's problem.
|
|
*/
|
|
|
|
foreach(sl, sortClause)
|
|
{
|
|
SortGroupClause *sc = (SortGroupClause *) lfirst(sl);
|
|
|
|
if (sc->tleSortGroupRef == tle->ressortgroupref)
|
|
{
|
|
SortGroupClause *grpc = copyObject(sc);
|
|
|
|
if (!toplevel)
|
|
grpc->nulls_first = false;
|
|
*flatresult = lappend(*flatresult, grpc);
|
|
found = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If no match in ORDER BY, just add it to the result using default
|
|
* sort/group semantics.
|
|
*/
|
|
if (!found)
|
|
*flatresult = addTargetToGroupList(pstate, tle,
|
|
*flatresult, *targetlist,
|
|
exprLocation(gexpr));
|
|
|
|
/*
|
|
* _something_ must have assigned us a sortgroupref by now...
|
|
*/
|
|
|
|
return tle->ressortgroupref;
|
|
}
|
|
|
|
/*
|
|
* Transform a list of expressions within a GROUP BY clause or grouping set.
|
|
*
|
|
* The list of expressions belongs to a single clause within which duplicates
|
|
* can be safely eliminated.
|
|
*
|
|
* Returns an integer list of ressortgroupref values.
|
|
*
|
|
* flatresult reference to flat list of SortGroupClause nodes
|
|
* pstate ParseState
|
|
* list nodes to transform
|
|
* targetlist reference to TargetEntry list
|
|
* sortClause ORDER BY clause (SortGroupClause nodes)
|
|
* exprKind expression kind
|
|
* useSQL99 SQL99 rather than SQL92 syntax
|
|
* toplevel false if within any grouping set
|
|
*/
|
|
static List *
|
|
transformGroupClauseList(List **flatresult,
|
|
ParseState *pstate, List *list,
|
|
List **targetlist, List *sortClause,
|
|
ParseExprKind exprKind, bool useSQL99, bool toplevel)
|
|
{
|
|
Bitmapset *seen_local = NULL;
|
|
List *result = NIL;
|
|
ListCell *gl;
|
|
|
|
foreach(gl, list)
|
|
{
|
|
Node *gexpr = (Node *) lfirst(gl);
|
|
|
|
Index ref = transformGroupClauseExpr(flatresult,
|
|
seen_local,
|
|
pstate,
|
|
gexpr,
|
|
targetlist,
|
|
sortClause,
|
|
exprKind,
|
|
useSQL99,
|
|
toplevel);
|
|
|
|
if (ref > 0)
|
|
{
|
|
seen_local = bms_add_member(seen_local, ref);
|
|
result = lappend_int(result, ref);
|
|
}
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Transform a grouping set and (recursively) its content.
|
|
*
|
|
* The grouping set might be a GROUPING SETS node with other grouping sets
|
|
* inside it, but SETS within SETS have already been flattened out before
|
|
* reaching here.
|
|
*
|
|
* Returns the transformed node, which now contains SIMPLE nodes with lists
|
|
* of ressortgrouprefs rather than expressions.
|
|
*
|
|
* flatresult reference to flat list of SortGroupClause nodes
|
|
* pstate ParseState
|
|
* gset grouping set to transform
|
|
* targetlist reference to TargetEntry list
|
|
* sortClause ORDER BY clause (SortGroupClause nodes)
|
|
* exprKind expression kind
|
|
* useSQL99 SQL99 rather than SQL92 syntax
|
|
* toplevel false if within any grouping set
|
|
*/
|
|
static Node *
|
|
transformGroupingSet(List **flatresult,
|
|
ParseState *pstate, GroupingSet *gset,
|
|
List **targetlist, List *sortClause,
|
|
ParseExprKind exprKind, bool useSQL99, bool toplevel)
|
|
{
|
|
ListCell *gl;
|
|
List *content = NIL;
|
|
|
|
Assert(toplevel || gset->kind != GROUPING_SET_SETS);
|
|
|
|
foreach(gl, gset->content)
|
|
{
|
|
Node *n = lfirst(gl);
|
|
|
|
if (IsA(n, List))
|
|
{
|
|
List *l = transformGroupClauseList(flatresult,
|
|
pstate, (List *) n,
|
|
targetlist, sortClause,
|
|
exprKind, useSQL99, false);
|
|
|
|
content = lappend(content, makeGroupingSet(GROUPING_SET_SIMPLE,
|
|
l,
|
|
exprLocation(n)));
|
|
}
|
|
else if (IsA(n, GroupingSet))
|
|
{
|
|
GroupingSet *gset2 = (GroupingSet *) lfirst(gl);
|
|
|
|
content = lappend(content, transformGroupingSet(flatresult,
|
|
pstate, gset2,
|
|
targetlist, sortClause,
|
|
exprKind, useSQL99, false));
|
|
}
|
|
else
|
|
{
|
|
Index ref = transformGroupClauseExpr(flatresult,
|
|
NULL,
|
|
pstate,
|
|
n,
|
|
targetlist,
|
|
sortClause,
|
|
exprKind,
|
|
useSQL99,
|
|
false);
|
|
|
|
content = lappend(content, makeGroupingSet(GROUPING_SET_SIMPLE,
|
|
list_make1_int(ref),
|
|
exprLocation(n)));
|
|
}
|
|
}
|
|
|
|
/* Arbitrarily cap the size of CUBE, which has exponential growth */
|
|
if (gset->kind == GROUPING_SET_CUBE)
|
|
{
|
|
if (list_length(content) > 12)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_TOO_MANY_COLUMNS),
|
|
errmsg("CUBE is limited to 12 elements"),
|
|
parser_errposition(pstate, gset->location)));
|
|
}
|
|
|
|
return (Node *) makeGroupingSet(gset->kind, content, gset->location);
|
|
}
|
|
|
|
|
|
/*
|
|
* transformGroupClause -
|
|
* transform a GROUP BY clause
|
|
*
|
|
* GROUP BY items will be added to the targetlist (as resjunk columns)
|
|
* if not already present, so the targetlist must be passed by reference.
|
|
*
|
|
* This is also used for window PARTITION BY clauses (which act almost the
|
|
* same, but are always interpreted per SQL99 rules).
|
|
*
|
|
* Grouping sets make this a lot more complex than it was. Our goal here is
|
|
* twofold: we make a flat list of SortGroupClause nodes referencing each
|
|
* distinct expression used for grouping, with those expressions added to the
|
|
* targetlist if needed. At the same time, we build the groupingSets tree,
|
|
* which stores only ressortgrouprefs as integer lists inside GroupingSet nodes
|
|
* (possibly nested, but limited in depth: a GROUPING_SET_SETS node can contain
|
|
* nested SIMPLE, CUBE or ROLLUP nodes, but not more sets - we flatten that
|
|
* out; while CUBE and ROLLUP can contain only SIMPLE nodes).
|
|
*
|
|
* We skip much of the hard work if there are no grouping sets.
|
|
*
|
|
* One subtlety is that the groupClause list can end up empty while the
|
|
* groupingSets list is not; this happens if there are only empty grouping
|
|
* sets, or an explicit GROUP BY (). This has the same effect as specifying
|
|
* aggregates or a HAVING clause with no GROUP BY; the output is one row per
|
|
* grouping set even if the input is empty.
|
|
*
|
|
* Returns the transformed (flat) groupClause.
|
|
*
|
|
* pstate ParseState
|
|
* grouplist clause to transform
|
|
* groupingSets reference to list to contain the grouping set tree
|
|
* targetlist reference to TargetEntry list
|
|
* sortClause ORDER BY clause (SortGroupClause nodes)
|
|
* exprKind expression kind
|
|
* useSQL99 SQL99 rather than SQL92 syntax
|
|
*/
|
|
List *
|
|
transformGroupClause(ParseState *pstate, List *grouplist, List **groupingSets,
|
|
List **targetlist, List *sortClause,
|
|
ParseExprKind exprKind, bool useSQL99)
|
|
{
|
|
List *result = NIL;
|
|
List *flat_grouplist;
|
|
List *gsets = NIL;
|
|
ListCell *gl;
|
|
bool hasGroupingSets = false;
|
|
Bitmapset *seen_local = NULL;
|
|
|
|
/*
|
|
* Recursively flatten implicit RowExprs. (Technically this is only needed
|
|
* for GROUP BY, per the syntax rules for grouping sets, but we do it
|
|
* anyway.)
|
|
*/
|
|
flat_grouplist = (List *) flatten_grouping_sets((Node *) grouplist,
|
|
true,
|
|
&hasGroupingSets);
|
|
|
|
/*
|
|
* If the list is now empty, but hasGroupingSets is true, it's because we
|
|
* elided redundant empty grouping sets. Restore a single empty grouping
|
|
* set to leave a canonical form: GROUP BY ()
|
|
*/
|
|
|
|
if (flat_grouplist == NIL && hasGroupingSets)
|
|
{
|
|
flat_grouplist = list_make1(makeGroupingSet(GROUPING_SET_EMPTY,
|
|
NIL,
|
|
exprLocation((Node *) grouplist)));
|
|
}
|
|
|
|
foreach(gl, flat_grouplist)
|
|
{
|
|
Node *gexpr = (Node *) lfirst(gl);
|
|
|
|
if (IsA(gexpr, GroupingSet))
|
|
{
|
|
GroupingSet *gset = (GroupingSet *) gexpr;
|
|
|
|
switch (gset->kind)
|
|
{
|
|
case GROUPING_SET_EMPTY:
|
|
gsets = lappend(gsets, gset);
|
|
break;
|
|
case GROUPING_SET_SIMPLE:
|
|
/* can't happen */
|
|
Assert(false);
|
|
break;
|
|
case GROUPING_SET_SETS:
|
|
case GROUPING_SET_CUBE:
|
|
case GROUPING_SET_ROLLUP:
|
|
gsets = lappend(gsets,
|
|
transformGroupingSet(&result,
|
|
pstate, gset,
|
|
targetlist, sortClause,
|
|
exprKind, useSQL99, true));
|
|
break;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
Index ref = transformGroupClauseExpr(&result, seen_local,
|
|
pstate, gexpr,
|
|
targetlist, sortClause,
|
|
exprKind, useSQL99, true);
|
|
|
|
if (ref > 0)
|
|
{
|
|
seen_local = bms_add_member(seen_local, ref);
|
|
if (hasGroupingSets)
|
|
gsets = lappend(gsets,
|
|
makeGroupingSet(GROUPING_SET_SIMPLE,
|
|
list_make1_int(ref),
|
|
exprLocation(gexpr)));
|
|
}
|
|
}
|
|
}
|
|
|
|
/* parser should prevent this */
|
|
Assert(gsets == NIL || groupingSets != NULL);
|
|
|
|
if (groupingSets)
|
|
*groupingSets = gsets;
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* transformSortClause -
|
|
* transform an ORDER BY clause
|
|
*
|
|
* ORDER BY items will be added to the targetlist (as resjunk columns)
|
|
* if not already present, so the targetlist must be passed by reference.
|
|
*
|
|
* This is also used for window and aggregate ORDER BY clauses (which act
|
|
* almost the same, but are always interpreted per SQL99 rules).
|
|
*/
|
|
List *
|
|
transformSortClause(ParseState *pstate,
|
|
List *orderlist,
|
|
List **targetlist,
|
|
ParseExprKind exprKind,
|
|
bool useSQL99)
|
|
{
|
|
List *sortlist = NIL;
|
|
ListCell *olitem;
|
|
|
|
foreach(olitem, orderlist)
|
|
{
|
|
SortBy *sortby = (SortBy *) lfirst(olitem);
|
|
TargetEntry *tle;
|
|
|
|
if (useSQL99)
|
|
tle = findTargetlistEntrySQL99(pstate, sortby->node,
|
|
targetlist, exprKind);
|
|
else
|
|
tle = findTargetlistEntrySQL92(pstate, sortby->node,
|
|
targetlist, exprKind);
|
|
|
|
sortlist = addTargetToSortList(pstate, tle,
|
|
sortlist, *targetlist, sortby);
|
|
}
|
|
|
|
return sortlist;
|
|
}
|
|
|
|
/*
|
|
* transformWindowDefinitions -
|
|
* transform window definitions (WindowDef to WindowClause)
|
|
*/
|
|
List *
|
|
transformWindowDefinitions(ParseState *pstate,
|
|
List *windowdefs,
|
|
List **targetlist)
|
|
{
|
|
List *result = NIL;
|
|
Index winref = 0;
|
|
ListCell *lc;
|
|
|
|
foreach(lc, windowdefs)
|
|
{
|
|
WindowDef *windef = (WindowDef *) lfirst(lc);
|
|
WindowClause *refwc = NULL;
|
|
List *partitionClause;
|
|
List *orderClause;
|
|
Oid rangeopfamily = InvalidOid;
|
|
Oid rangeopcintype = InvalidOid;
|
|
WindowClause *wc;
|
|
|
|
winref++;
|
|
|
|
/*
|
|
* Check for duplicate window names.
|
|
*/
|
|
if (windef->name &&
|
|
findWindowClause(result, windef->name) != NULL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WINDOWING_ERROR),
|
|
errmsg("window \"%s\" is already defined", windef->name),
|
|
parser_errposition(pstate, windef->location)));
|
|
|
|
/*
|
|
* If it references a previous window, look that up.
|
|
*/
|
|
if (windef->refname)
|
|
{
|
|
refwc = findWindowClause(result, windef->refname);
|
|
if (refwc == NULL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_OBJECT),
|
|
errmsg("window \"%s\" does not exist",
|
|
windef->refname),
|
|
parser_errposition(pstate, windef->location)));
|
|
}
|
|
|
|
/*
|
|
* Transform PARTITION and ORDER specs, if any. These are treated
|
|
* almost exactly like top-level GROUP BY and ORDER BY clauses,
|
|
* including the special handling of nondefault operator semantics.
|
|
*/
|
|
orderClause = transformSortClause(pstate,
|
|
windef->orderClause,
|
|
targetlist,
|
|
EXPR_KIND_WINDOW_ORDER,
|
|
true /* force SQL99 rules */ );
|
|
partitionClause = transformGroupClause(pstate,
|
|
windef->partitionClause,
|
|
NULL,
|
|
targetlist,
|
|
orderClause,
|
|
EXPR_KIND_WINDOW_PARTITION,
|
|
true /* force SQL99 rules */ );
|
|
|
|
/*
|
|
* And prepare the new WindowClause.
|
|
*/
|
|
wc = makeNode(WindowClause);
|
|
wc->name = windef->name;
|
|
wc->refname = windef->refname;
|
|
|
|
/*
|
|
* Per spec, a windowdef that references a previous one copies the
|
|
* previous partition clause (and mustn't specify its own). It can
|
|
* specify its own ordering clause, but only if the previous one had
|
|
* none. It always specifies its own frame clause, and the previous
|
|
* one must not have a frame clause. Yeah, it's bizarre that each of
|
|
* these cases works differently, but SQL:2008 says so; see 7.11
|
|
* <window clause> syntax rule 10 and general rule 1. The frame
|
|
* clause rule is especially bizarre because it makes "OVER foo"
|
|
* different from "OVER (foo)", and requires the latter to throw an
|
|
* error if foo has a nondefault frame clause. Well, ours not to
|
|
* reason why, but we do go out of our way to throw a useful error
|
|
* message for such cases.
|
|
*/
|
|
if (refwc)
|
|
{
|
|
if (partitionClause)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WINDOWING_ERROR),
|
|
errmsg("cannot override PARTITION BY clause of window \"%s\"",
|
|
windef->refname),
|
|
parser_errposition(pstate, windef->location)));
|
|
wc->partitionClause = copyObject(refwc->partitionClause);
|
|
}
|
|
else
|
|
wc->partitionClause = partitionClause;
|
|
if (refwc)
|
|
{
|
|
if (orderClause && refwc->orderClause)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WINDOWING_ERROR),
|
|
errmsg("cannot override ORDER BY clause of window \"%s\"",
|
|
windef->refname),
|
|
parser_errposition(pstate, windef->location)));
|
|
if (orderClause)
|
|
{
|
|
wc->orderClause = orderClause;
|
|
wc->copiedOrder = false;
|
|
}
|
|
else
|
|
{
|
|
wc->orderClause = copyObject(refwc->orderClause);
|
|
wc->copiedOrder = true;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
wc->orderClause = orderClause;
|
|
wc->copiedOrder = false;
|
|
}
|
|
if (refwc && refwc->frameOptions != FRAMEOPTION_DEFAULTS)
|
|
{
|
|
/*
|
|
* Use this message if this is a WINDOW clause, or if it's an OVER
|
|
* clause that includes ORDER BY or framing clauses. (We already
|
|
* rejected PARTITION BY above, so no need to check that.)
|
|
*/
|
|
if (windef->name ||
|
|
orderClause || windef->frameOptions != FRAMEOPTION_DEFAULTS)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WINDOWING_ERROR),
|
|
errmsg("cannot copy window \"%s\" because it has a frame clause",
|
|
windef->refname),
|
|
parser_errposition(pstate, windef->location)));
|
|
/* Else this clause is just OVER (foo), so say this: */
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WINDOWING_ERROR),
|
|
errmsg("cannot copy window \"%s\" because it has a frame clause",
|
|
windef->refname),
|
|
errhint("Omit the parentheses in this OVER clause."),
|
|
parser_errposition(pstate, windef->location)));
|
|
}
|
|
wc->frameOptions = windef->frameOptions;
|
|
|
|
/*
|
|
* RANGE offset PRECEDING/FOLLOWING requires exactly one ORDER BY
|
|
* column; check that and get its sort opfamily info.
|
|
*/
|
|
if ((wc->frameOptions & FRAMEOPTION_RANGE) &&
|
|
(wc->frameOptions & (FRAMEOPTION_START_OFFSET |
|
|
FRAMEOPTION_END_OFFSET)))
|
|
{
|
|
SortGroupClause *sortcl;
|
|
Node *sortkey;
|
|
int16 rangestrategy;
|
|
|
|
if (list_length(wc->orderClause) != 1)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WINDOWING_ERROR),
|
|
errmsg("RANGE with offset PRECEDING/FOLLOWING requires exactly one ORDER BY column"),
|
|
parser_errposition(pstate, windef->location)));
|
|
sortcl = castNode(SortGroupClause, linitial(wc->orderClause));
|
|
sortkey = get_sortgroupclause_expr(sortcl, *targetlist);
|
|
/* Find the sort operator in pg_amop */
|
|
if (!get_ordering_op_properties(sortcl->sortop,
|
|
&rangeopfamily,
|
|
&rangeopcintype,
|
|
&rangestrategy))
|
|
elog(ERROR, "operator %u is not a valid ordering operator",
|
|
sortcl->sortop);
|
|
/* Record properties of sort ordering */
|
|
wc->inRangeColl = exprCollation(sortkey);
|
|
wc->inRangeAsc = (rangestrategy == BTLessStrategyNumber);
|
|
wc->inRangeNullsFirst = sortcl->nulls_first;
|
|
}
|
|
|
|
/* Per spec, GROUPS mode requires an ORDER BY clause */
|
|
if (wc->frameOptions & FRAMEOPTION_GROUPS)
|
|
{
|
|
if (wc->orderClause == NIL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WINDOWING_ERROR),
|
|
errmsg("GROUPS mode requires an ORDER BY clause"),
|
|
parser_errposition(pstate, windef->location)));
|
|
}
|
|
|
|
/* Process frame offset expressions */
|
|
wc->startOffset = transformFrameOffset(pstate, wc->frameOptions,
|
|
rangeopfamily, rangeopcintype,
|
|
&wc->startInRangeFunc,
|
|
windef->startOffset);
|
|
wc->endOffset = transformFrameOffset(pstate, wc->frameOptions,
|
|
rangeopfamily, rangeopcintype,
|
|
&wc->endInRangeFunc,
|
|
windef->endOffset);
|
|
wc->winref = winref;
|
|
|
|
result = lappend(result, wc);
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* transformDistinctClause -
|
|
* transform a DISTINCT clause
|
|
*
|
|
* Since we may need to add items to the query's targetlist, that list
|
|
* is passed by reference.
|
|
*
|
|
* As with GROUP BY, we absorb the sorting semantics of ORDER BY as much as
|
|
* possible into the distinctClause. This avoids a possible need to re-sort,
|
|
* and allows the user to choose the equality semantics used by DISTINCT,
|
|
* should she be working with a datatype that has more than one equality
|
|
* operator.
|
|
*
|
|
* is_agg is true if we are transforming an aggregate(DISTINCT ...)
|
|
* function call. This does not affect any behavior, only the phrasing
|
|
* of error messages.
|
|
*/
|
|
List *
|
|
transformDistinctClause(ParseState *pstate,
|
|
List **targetlist, List *sortClause, bool is_agg)
|
|
{
|
|
List *result = NIL;
|
|
ListCell *slitem;
|
|
ListCell *tlitem;
|
|
|
|
/*
|
|
* The distinctClause should consist of all ORDER BY items followed by all
|
|
* other non-resjunk targetlist items. There must not be any resjunk
|
|
* ORDER BY items --- that would imply that we are sorting by a value that
|
|
* isn't necessarily unique within a DISTINCT group, so the results
|
|
* wouldn't be well-defined. This construction ensures we follow the rule
|
|
* that sortClause and distinctClause match; in fact the sortClause will
|
|
* always be a prefix of distinctClause.
|
|
*
|
|
* Note a corner case: the same TLE could be in the ORDER BY list multiple
|
|
* times with different sortops. We have to include it in the
|
|
* distinctClause the same way to preserve the prefix property. The net
|
|
* effect will be that the TLE value will be made unique according to both
|
|
* sortops.
|
|
*/
|
|
foreach(slitem, sortClause)
|
|
{
|
|
SortGroupClause *scl = (SortGroupClause *) lfirst(slitem);
|
|
TargetEntry *tle = get_sortgroupclause_tle(scl, *targetlist);
|
|
|
|
if (tle->resjunk)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
|
|
is_agg ?
|
|
errmsg("in an aggregate with DISTINCT, ORDER BY expressions must appear in argument list") :
|
|
errmsg("for SELECT DISTINCT, ORDER BY expressions must appear in select list"),
|
|
parser_errposition(pstate,
|
|
exprLocation((Node *) tle->expr))));
|
|
result = lappend(result, copyObject(scl));
|
|
}
|
|
|
|
/*
|
|
* Now add any remaining non-resjunk tlist items, using default sort/group
|
|
* semantics for their data types.
|
|
*/
|
|
foreach(tlitem, *targetlist)
|
|
{
|
|
TargetEntry *tle = (TargetEntry *) lfirst(tlitem);
|
|
|
|
if (tle->resjunk)
|
|
continue; /* ignore junk */
|
|
result = addTargetToGroupList(pstate, tle,
|
|
result, *targetlist,
|
|
exprLocation((Node *) tle->expr));
|
|
}
|
|
|
|
/*
|
|
* Complain if we found nothing to make DISTINCT. Returning an empty list
|
|
* would cause the parsed Query to look like it didn't have DISTINCT, with
|
|
* results that would probably surprise the user. Note: this case is
|
|
* presently impossible for aggregates because of grammar restrictions,
|
|
* but we check anyway.
|
|
*/
|
|
if (result == NIL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
is_agg ?
|
|
errmsg("an aggregate with DISTINCT must have at least one argument") :
|
|
errmsg("SELECT DISTINCT must have at least one column")));
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* transformDistinctOnClause -
|
|
* transform a DISTINCT ON clause
|
|
*
|
|
* Since we may need to add items to the query's targetlist, that list
|
|
* is passed by reference.
|
|
*
|
|
* As with GROUP BY, we absorb the sorting semantics of ORDER BY as much as
|
|
* possible into the distinctClause. This avoids a possible need to re-sort,
|
|
* and allows the user to choose the equality semantics used by DISTINCT,
|
|
* should she be working with a datatype that has more than one equality
|
|
* operator.
|
|
*/
|
|
List *
|
|
transformDistinctOnClause(ParseState *pstate, List *distinctlist,
|
|
List **targetlist, List *sortClause)
|
|
{
|
|
List *result = NIL;
|
|
List *sortgrouprefs = NIL;
|
|
bool skipped_sortitem;
|
|
ListCell *lc;
|
|
ListCell *lc2;
|
|
|
|
/*
|
|
* Add all the DISTINCT ON expressions to the tlist (if not already
|
|
* present, they are added as resjunk items). Assign sortgroupref numbers
|
|
* to them, and make a list of these numbers. (NB: we rely below on the
|
|
* sortgrouprefs list being one-for-one with the original distinctlist.
|
|
* Also notice that we could have duplicate DISTINCT ON expressions and
|
|
* hence duplicate entries in sortgrouprefs.)
|
|
*/
|
|
foreach(lc, distinctlist)
|
|
{
|
|
Node *dexpr = (Node *) lfirst(lc);
|
|
int sortgroupref;
|
|
TargetEntry *tle;
|
|
|
|
tle = findTargetlistEntrySQL92(pstate, dexpr, targetlist,
|
|
EXPR_KIND_DISTINCT_ON);
|
|
sortgroupref = assignSortGroupRef(tle, *targetlist);
|
|
sortgrouprefs = lappend_int(sortgrouprefs, sortgroupref);
|
|
}
|
|
|
|
/*
|
|
* If the user writes both DISTINCT ON and ORDER BY, adopt the sorting
|
|
* semantics from ORDER BY items that match DISTINCT ON items, and also
|
|
* adopt their column sort order. We insist that the distinctClause and
|
|
* sortClause match, so throw error if we find the need to add any more
|
|
* distinctClause items after we've skipped an ORDER BY item that wasn't
|
|
* in DISTINCT ON.
|
|
*/
|
|
skipped_sortitem = false;
|
|
foreach(lc, sortClause)
|
|
{
|
|
SortGroupClause *scl = (SortGroupClause *) lfirst(lc);
|
|
|
|
if (list_member_int(sortgrouprefs, scl->tleSortGroupRef))
|
|
{
|
|
if (skipped_sortitem)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
|
|
errmsg("SELECT DISTINCT ON expressions must match initial ORDER BY expressions"),
|
|
parser_errposition(pstate,
|
|
get_matching_location(scl->tleSortGroupRef,
|
|
sortgrouprefs,
|
|
distinctlist))));
|
|
else
|
|
result = lappend(result, copyObject(scl));
|
|
}
|
|
else
|
|
skipped_sortitem = true;
|
|
}
|
|
|
|
/*
|
|
* Now add any remaining DISTINCT ON items, using default sort/group
|
|
* semantics for their data types. (Note: this is pretty questionable; if
|
|
* the ORDER BY list doesn't include all the DISTINCT ON items and more
|
|
* besides, you certainly aren't using DISTINCT ON in the intended way,
|
|
* and you probably aren't going to get consistent results. It might be
|
|
* better to throw an error or warning here. But historically we've
|
|
* allowed it, so keep doing so.)
|
|
*/
|
|
forboth(lc, distinctlist, lc2, sortgrouprefs)
|
|
{
|
|
Node *dexpr = (Node *) lfirst(lc);
|
|
int sortgroupref = lfirst_int(lc2);
|
|
TargetEntry *tle = get_sortgroupref_tle(sortgroupref, *targetlist);
|
|
|
|
if (targetIsInSortList(tle, InvalidOid, result))
|
|
continue; /* already in list (with some semantics) */
|
|
if (skipped_sortitem)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
|
|
errmsg("SELECT DISTINCT ON expressions must match initial ORDER BY expressions"),
|
|
parser_errposition(pstate, exprLocation(dexpr))));
|
|
result = addTargetToGroupList(pstate, tle,
|
|
result, *targetlist,
|
|
exprLocation(dexpr));
|
|
}
|
|
|
|
/*
|
|
* An empty result list is impossible here because of grammar
|
|
* restrictions.
|
|
*/
|
|
Assert(result != NIL);
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* get_matching_location
|
|
* Get the exprLocation of the exprs member corresponding to the
|
|
* (first) member of sortgrouprefs that equals sortgroupref.
|
|
*
|
|
* This is used so that we can point at a troublesome DISTINCT ON entry.
|
|
* (Note that we need to use the original untransformed DISTINCT ON list
|
|
* item, as whatever TLE it corresponds to will very possibly have a
|
|
* parse location pointing to some matching entry in the SELECT list
|
|
* or ORDER BY list.)
|
|
*/
|
|
static int
|
|
get_matching_location(int sortgroupref, List *sortgrouprefs, List *exprs)
|
|
{
|
|
ListCell *lcs;
|
|
ListCell *lce;
|
|
|
|
forboth(lcs, sortgrouprefs, lce, exprs)
|
|
{
|
|
if (lfirst_int(lcs) == sortgroupref)
|
|
return exprLocation((Node *) lfirst(lce));
|
|
}
|
|
/* if no match, caller blew it */
|
|
elog(ERROR, "get_matching_location: no matching sortgroupref");
|
|
return -1; /* keep compiler quiet */
|
|
}
|
|
|
|
/*
|
|
* resolve_unique_index_expr
|
|
* Infer a unique index from a list of indexElems, for ON
|
|
* CONFLICT clause
|
|
*
|
|
* Perform parse analysis of expressions and columns appearing within ON
|
|
* CONFLICT clause. During planning, the returned list of expressions is used
|
|
* to infer which unique index to use.
|
|
*/
|
|
static List *
|
|
resolve_unique_index_expr(ParseState *pstate, InferClause *infer,
|
|
Relation heapRel)
|
|
{
|
|
List *result = NIL;
|
|
ListCell *l;
|
|
|
|
foreach(l, infer->indexElems)
|
|
{
|
|
IndexElem *ielem = (IndexElem *) lfirst(l);
|
|
InferenceElem *pInfer = makeNode(InferenceElem);
|
|
Node *parse;
|
|
|
|
/*
|
|
* Raw grammar re-uses CREATE INDEX infrastructure for unique index
|
|
* inference clause, and so will accept opclasses by name and so on.
|
|
*
|
|
* Make no attempt to match ASC or DESC ordering or NULLS FIRST/NULLS
|
|
* LAST ordering, since those are not significant for inference
|
|
* purposes (any unique index matching the inference specification in
|
|
* other regards is accepted indifferently). Actively reject this as
|
|
* wrong-headed.
|
|
*/
|
|
if (ielem->ordering != SORTBY_DEFAULT)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
|
|
errmsg("ASC/DESC is not allowed in ON CONFLICT clause"),
|
|
parser_errposition(pstate,
|
|
exprLocation((Node *) infer))));
|
|
if (ielem->nulls_ordering != SORTBY_NULLS_DEFAULT)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
|
|
errmsg("NULLS FIRST/LAST is not allowed in ON CONFLICT clause"),
|
|
parser_errposition(pstate,
|
|
exprLocation((Node *) infer))));
|
|
|
|
if (!ielem->expr)
|
|
{
|
|
/* Simple index attribute */
|
|
ColumnRef *n;
|
|
|
|
/*
|
|
* Grammar won't have built raw expression for us in event of
|
|
* plain column reference. Create one directly, and perform
|
|
* expression transformation. Planner expects this, and performs
|
|
* its own normalization for the purposes of matching against
|
|
* pg_index.
|
|
*/
|
|
n = makeNode(ColumnRef);
|
|
n->fields = list_make1(makeString(ielem->name));
|
|
/* Location is approximately that of inference specification */
|
|
n->location = infer->location;
|
|
parse = (Node *) n;
|
|
}
|
|
else
|
|
{
|
|
/* Do parse transformation of the raw expression */
|
|
parse = (Node *) ielem->expr;
|
|
}
|
|
|
|
/*
|
|
* transformExpr() will reject subqueries, aggregates, window
|
|
* functions, and SRFs, based on being passed
|
|
* EXPR_KIND_INDEX_EXPRESSION. So we needn't worry about those
|
|
* further ... not that they would match any available index
|
|
* expression anyway.
|
|
*/
|
|
pInfer->expr = transformExpr(pstate, parse, EXPR_KIND_INDEX_EXPRESSION);
|
|
|
|
/* Perform lookup of collation and operator class as required */
|
|
if (!ielem->collation)
|
|
pInfer->infercollid = InvalidOid;
|
|
else
|
|
pInfer->infercollid = LookupCollation(pstate, ielem->collation,
|
|
exprLocation(pInfer->expr));
|
|
|
|
if (!ielem->opclass)
|
|
pInfer->inferopclass = InvalidOid;
|
|
else
|
|
pInfer->inferopclass = get_opclass_oid(BTREE_AM_OID,
|
|
ielem->opclass, false);
|
|
|
|
result = lappend(result, pInfer);
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* transformOnConflictArbiter -
|
|
* transform arbiter expressions in an ON CONFLICT clause.
|
|
*
|
|
* Transformed expressions used to infer one unique index relation to serve as
|
|
* an ON CONFLICT arbiter. Partial unique indexes may be inferred using WHERE
|
|
* clause from inference specification clause.
|
|
*/
|
|
void
|
|
transformOnConflictArbiter(ParseState *pstate,
|
|
OnConflictClause *onConflictClause,
|
|
List **arbiterExpr, Node **arbiterWhere,
|
|
Oid *constraint)
|
|
{
|
|
InferClause *infer = onConflictClause->infer;
|
|
|
|
*arbiterExpr = NIL;
|
|
*arbiterWhere = NULL;
|
|
*constraint = InvalidOid;
|
|
|
|
if (onConflictClause->action == ONCONFLICT_UPDATE && !infer)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("ON CONFLICT DO UPDATE requires inference specification or constraint name"),
|
|
errhint("For example, ON CONFLICT (column_name)."),
|
|
parser_errposition(pstate,
|
|
exprLocation((Node *) onConflictClause))));
|
|
|
|
/*
|
|
* To simplify certain aspects of its design, speculative insertion into
|
|
* system catalogs is disallowed
|
|
*/
|
|
if (IsCatalogRelation(pstate->p_target_relation))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("ON CONFLICT is not supported with system catalog tables"),
|
|
parser_errposition(pstate,
|
|
exprLocation((Node *) onConflictClause))));
|
|
|
|
/* Same applies to table used by logical decoding as catalog table */
|
|
if (RelationIsUsedAsCatalogTable(pstate->p_target_relation))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("ON CONFLICT is not supported on table \"%s\" used as a catalog table",
|
|
RelationGetRelationName(pstate->p_target_relation)),
|
|
parser_errposition(pstate,
|
|
exprLocation((Node *) onConflictClause))));
|
|
|
|
/* ON CONFLICT DO NOTHING does not require an inference clause */
|
|
if (infer)
|
|
{
|
|
List *save_namespace;
|
|
|
|
/*
|
|
* While we process the arbiter expressions, accept only non-qualified
|
|
* references to the target table. Hide any other relations.
|
|
*/
|
|
save_namespace = pstate->p_namespace;
|
|
pstate->p_namespace = NIL;
|
|
addRTEtoQuery(pstate, pstate->p_target_rangetblentry,
|
|
false, false, true);
|
|
|
|
if (infer->indexElems)
|
|
*arbiterExpr = resolve_unique_index_expr(pstate, infer,
|
|
pstate->p_target_relation);
|
|
|
|
/*
|
|
* Handling inference WHERE clause (for partial unique index
|
|
* inference)
|
|
*/
|
|
if (infer->whereClause)
|
|
*arbiterWhere = transformExpr(pstate, infer->whereClause,
|
|
EXPR_KIND_INDEX_PREDICATE);
|
|
|
|
pstate->p_namespace = save_namespace;
|
|
|
|
/*
|
|
* If the arbiter is specified by constraint name, get the constraint
|
|
* OID and mark the constrained columns as requiring SELECT privilege,
|
|
* in the same way as would have happened if the arbiter had been
|
|
* specified by explicit reference to the constraint's index columns.
|
|
*/
|
|
if (infer->conname)
|
|
{
|
|
Oid relid = RelationGetRelid(pstate->p_target_relation);
|
|
RangeTblEntry *rte = pstate->p_target_rangetblentry;
|
|
Bitmapset *conattnos;
|
|
|
|
conattnos = get_relation_constraint_attnos(relid, infer->conname,
|
|
false, constraint);
|
|
|
|
/* Make sure the rel as a whole is marked for SELECT access */
|
|
rte->requiredPerms |= ACL_SELECT;
|
|
/* Mark the constrained columns as requiring SELECT access */
|
|
rte->selectedCols = bms_add_members(rte->selectedCols, conattnos);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* It's convenient to form a list of expressions based on the
|
|
* representation used by CREATE INDEX, since the same restrictions are
|
|
* appropriate (e.g. on subqueries). However, from here on, a dedicated
|
|
* primnode representation is used for inference elements, and so
|
|
* assign_query_collations() can be trusted to do the right thing with the
|
|
* post parse analysis query tree inference clause representation.
|
|
*/
|
|
}
|
|
|
|
/*
|
|
* addTargetToSortList
|
|
* If the given targetlist entry isn't already in the SortGroupClause
|
|
* list, add it to the end of the list, using the given sort ordering
|
|
* info.
|
|
*
|
|
* Returns the updated SortGroupClause list.
|
|
*/
|
|
List *
|
|
addTargetToSortList(ParseState *pstate, TargetEntry *tle,
|
|
List *sortlist, List *targetlist, SortBy *sortby)
|
|
{
|
|
Oid restype = exprType((Node *) tle->expr);
|
|
Oid sortop;
|
|
Oid eqop;
|
|
bool hashable;
|
|
bool reverse;
|
|
int location;
|
|
ParseCallbackState pcbstate;
|
|
|
|
/* if tlist item is an UNKNOWN literal, change it to TEXT */
|
|
if (restype == UNKNOWNOID)
|
|
{
|
|
tle->expr = (Expr *) coerce_type(pstate, (Node *) tle->expr,
|
|
restype, TEXTOID, -1,
|
|
COERCION_IMPLICIT,
|
|
COERCE_IMPLICIT_CAST,
|
|
-1);
|
|
restype = TEXTOID;
|
|
}
|
|
|
|
/*
|
|
* Rather than clutter the API of get_sort_group_operators and the other
|
|
* functions we're about to use, make use of error context callback to
|
|
* mark any error reports with a parse position. We point to the operator
|
|
* location if present, else to the expression being sorted. (NB: use the
|
|
* original untransformed expression here; the TLE entry might well point
|
|
* at a duplicate expression in the regular SELECT list.)
|
|
*/
|
|
location = sortby->location;
|
|
if (location < 0)
|
|
location = exprLocation(sortby->node);
|
|
setup_parser_errposition_callback(&pcbstate, pstate, location);
|
|
|
|
/* determine the sortop, eqop, and directionality */
|
|
switch (sortby->sortby_dir)
|
|
{
|
|
case SORTBY_DEFAULT:
|
|
case SORTBY_ASC:
|
|
get_sort_group_operators(restype,
|
|
true, true, false,
|
|
&sortop, &eqop, NULL,
|
|
&hashable);
|
|
reverse = false;
|
|
break;
|
|
case SORTBY_DESC:
|
|
get_sort_group_operators(restype,
|
|
false, true, true,
|
|
NULL, &eqop, &sortop,
|
|
&hashable);
|
|
reverse = true;
|
|
break;
|
|
case SORTBY_USING:
|
|
Assert(sortby->useOp != NIL);
|
|
sortop = compatible_oper_opid(sortby->useOp,
|
|
restype,
|
|
restype,
|
|
false);
|
|
|
|
/*
|
|
* Verify it's a valid ordering operator, fetch the corresponding
|
|
* equality operator, and determine whether to consider it like
|
|
* ASC or DESC.
|
|
*/
|
|
eqop = get_equality_op_for_ordering_op(sortop, &reverse);
|
|
if (!OidIsValid(eqop))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
|
|
errmsg("operator %s is not a valid ordering operator",
|
|
strVal(llast(sortby->useOp))),
|
|
errhint("Ordering operators must be \"<\" or \">\" members of btree operator families.")));
|
|
|
|
/*
|
|
* Also see if the equality operator is hashable.
|
|
*/
|
|
hashable = op_hashjoinable(eqop, restype);
|
|
break;
|
|
default:
|
|
elog(ERROR, "unrecognized sortby_dir: %d", sortby->sortby_dir);
|
|
sortop = InvalidOid; /* keep compiler quiet */
|
|
eqop = InvalidOid;
|
|
hashable = false;
|
|
reverse = false;
|
|
break;
|
|
}
|
|
|
|
cancel_parser_errposition_callback(&pcbstate);
|
|
|
|
/* avoid making duplicate sortlist entries */
|
|
if (!targetIsInSortList(tle, sortop, sortlist))
|
|
{
|
|
SortGroupClause *sortcl = makeNode(SortGroupClause);
|
|
|
|
sortcl->tleSortGroupRef = assignSortGroupRef(tle, targetlist);
|
|
|
|
sortcl->eqop = eqop;
|
|
sortcl->sortop = sortop;
|
|
sortcl->hashable = hashable;
|
|
|
|
switch (sortby->sortby_nulls)
|
|
{
|
|
case SORTBY_NULLS_DEFAULT:
|
|
/* NULLS FIRST is default for DESC; other way for ASC */
|
|
sortcl->nulls_first = reverse;
|
|
break;
|
|
case SORTBY_NULLS_FIRST:
|
|
sortcl->nulls_first = true;
|
|
break;
|
|
case SORTBY_NULLS_LAST:
|
|
sortcl->nulls_first = false;
|
|
break;
|
|
default:
|
|
elog(ERROR, "unrecognized sortby_nulls: %d",
|
|
sortby->sortby_nulls);
|
|
break;
|
|
}
|
|
|
|
sortlist = lappend(sortlist, sortcl);
|
|
}
|
|
|
|
return sortlist;
|
|
}
|
|
|
|
/*
|
|
* addTargetToGroupList
|
|
* If the given targetlist entry isn't already in the SortGroupClause
|
|
* list, add it to the end of the list, using default sort/group
|
|
* semantics.
|
|
*
|
|
* This is very similar to addTargetToSortList, except that we allow the
|
|
* case where only a grouping (equality) operator can be found, and that
|
|
* the TLE is considered "already in the list" if it appears there with any
|
|
* sorting semantics.
|
|
*
|
|
* location is the parse location to be fingered in event of trouble. Note
|
|
* that we can't rely on exprLocation(tle->expr), because that might point
|
|
* to a SELECT item that matches the GROUP BY item; it'd be pretty confusing
|
|
* to report such a location.
|
|
*
|
|
* Returns the updated SortGroupClause list.
|
|
*/
|
|
static List *
|
|
addTargetToGroupList(ParseState *pstate, TargetEntry *tle,
|
|
List *grouplist, List *targetlist, int location)
|
|
{
|
|
Oid restype = exprType((Node *) tle->expr);
|
|
|
|
/* if tlist item is an UNKNOWN literal, change it to TEXT */
|
|
if (restype == UNKNOWNOID)
|
|
{
|
|
tle->expr = (Expr *) coerce_type(pstate, (Node *) tle->expr,
|
|
restype, TEXTOID, -1,
|
|
COERCION_IMPLICIT,
|
|
COERCE_IMPLICIT_CAST,
|
|
-1);
|
|
restype = TEXTOID;
|
|
}
|
|
|
|
/* avoid making duplicate grouplist entries */
|
|
if (!targetIsInSortList(tle, InvalidOid, grouplist))
|
|
{
|
|
SortGroupClause *grpcl = makeNode(SortGroupClause);
|
|
Oid sortop;
|
|
Oid eqop;
|
|
bool hashable;
|
|
ParseCallbackState pcbstate;
|
|
|
|
setup_parser_errposition_callback(&pcbstate, pstate, location);
|
|
|
|
/* determine the eqop and optional sortop */
|
|
get_sort_group_operators(restype,
|
|
false, true, false,
|
|
&sortop, &eqop, NULL,
|
|
&hashable);
|
|
|
|
cancel_parser_errposition_callback(&pcbstate);
|
|
|
|
grpcl->tleSortGroupRef = assignSortGroupRef(tle, targetlist);
|
|
grpcl->eqop = eqop;
|
|
grpcl->sortop = sortop;
|
|
grpcl->nulls_first = false; /* OK with or without sortop */
|
|
grpcl->hashable = hashable;
|
|
|
|
grouplist = lappend(grouplist, grpcl);
|
|
}
|
|
|
|
return grouplist;
|
|
}
|
|
|
|
/*
|
|
* assignSortGroupRef
|
|
* Assign the targetentry an unused ressortgroupref, if it doesn't
|
|
* already have one. Return the assigned or pre-existing refnumber.
|
|
*
|
|
* 'tlist' is the targetlist containing (or to contain) the given targetentry.
|
|
*/
|
|
Index
|
|
assignSortGroupRef(TargetEntry *tle, List *tlist)
|
|
{
|
|
Index maxRef;
|
|
ListCell *l;
|
|
|
|
if (tle->ressortgroupref) /* already has one? */
|
|
return tle->ressortgroupref;
|
|
|
|
/* easiest way to pick an unused refnumber: max used + 1 */
|
|
maxRef = 0;
|
|
foreach(l, tlist)
|
|
{
|
|
Index ref = ((TargetEntry *) lfirst(l))->ressortgroupref;
|
|
|
|
if (ref > maxRef)
|
|
maxRef = ref;
|
|
}
|
|
tle->ressortgroupref = maxRef + 1;
|
|
return tle->ressortgroupref;
|
|
}
|
|
|
|
/*
|
|
* targetIsInSortList
|
|
* Is the given target item already in the sortlist?
|
|
* If sortop is not InvalidOid, also test for a match to the sortop.
|
|
*
|
|
* It is not an oversight that this function ignores the nulls_first flag.
|
|
* We check sortop when determining if an ORDER BY item is redundant with
|
|
* earlier ORDER BY items, because it's conceivable that "ORDER BY
|
|
* foo USING <, foo USING <<<" is not redundant, if <<< distinguishes
|
|
* values that < considers equal. We need not check nulls_first
|
|
* however, because a lower-order column with the same sortop but
|
|
* opposite nulls direction is redundant. Also, we can consider
|
|
* ORDER BY foo ASC, foo DESC redundant, so check for a commutator match.
|
|
*
|
|
* Works for both ordering and grouping lists (sortop would normally be
|
|
* InvalidOid when considering grouping). Note that the main reason we need
|
|
* this routine (and not just a quick test for nonzeroness of ressortgroupref)
|
|
* is that a TLE might be in only one of the lists.
|
|
*/
|
|
bool
|
|
targetIsInSortList(TargetEntry *tle, Oid sortop, List *sortList)
|
|
{
|
|
Index ref = tle->ressortgroupref;
|
|
ListCell *l;
|
|
|
|
/* no need to scan list if tle has no marker */
|
|
if (ref == 0)
|
|
return false;
|
|
|
|
foreach(l, sortList)
|
|
{
|
|
SortGroupClause *scl = (SortGroupClause *) lfirst(l);
|
|
|
|
if (scl->tleSortGroupRef == ref &&
|
|
(sortop == InvalidOid ||
|
|
sortop == scl->sortop ||
|
|
sortop == get_commutator(scl->sortop)))
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* findWindowClause
|
|
* Find the named WindowClause in the list, or return NULL if not there
|
|
*/
|
|
static WindowClause *
|
|
findWindowClause(List *wclist, const char *name)
|
|
{
|
|
ListCell *l;
|
|
|
|
foreach(l, wclist)
|
|
{
|
|
WindowClause *wc = (WindowClause *) lfirst(l);
|
|
|
|
if (wc->name && strcmp(wc->name, name) == 0)
|
|
return wc;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* transformFrameOffset
|
|
* Process a window frame offset expression
|
|
*
|
|
* In RANGE mode, rangeopfamily is the sort opfamily for the input ORDER BY
|
|
* column, and rangeopcintype is the input data type the sort operator is
|
|
* registered with. We expect the in_range function to be registered with
|
|
* that same type. (In binary-compatible cases, it might be different from
|
|
* the input column's actual type, so we can't use that for the lookups.)
|
|
* We'll return the OID of the in_range function to *inRangeFunc.
|
|
*/
|
|
static Node *
|
|
transformFrameOffset(ParseState *pstate, int frameOptions,
|
|
Oid rangeopfamily, Oid rangeopcintype, Oid *inRangeFunc,
|
|
Node *clause)
|
|
{
|
|
const char *constructName = NULL;
|
|
Node *node;
|
|
|
|
*inRangeFunc = InvalidOid; /* default result */
|
|
|
|
/* Quick exit if no offset expression */
|
|
if (clause == NULL)
|
|
return NULL;
|
|
|
|
if (frameOptions & FRAMEOPTION_ROWS)
|
|
{
|
|
/* Transform the raw expression tree */
|
|
node = transformExpr(pstate, clause, EXPR_KIND_WINDOW_FRAME_ROWS);
|
|
|
|
/*
|
|
* Like LIMIT clause, simply coerce to int8
|
|
*/
|
|
constructName = "ROWS";
|
|
node = coerce_to_specific_type(pstate, node, INT8OID, constructName);
|
|
}
|
|
else if (frameOptions & FRAMEOPTION_RANGE)
|
|
{
|
|
/*
|
|
* We must look up the in_range support function that's to be used,
|
|
* possibly choosing one of several, and coerce the "offset" value to
|
|
* the appropriate input type.
|
|
*/
|
|
Oid nodeType;
|
|
Oid preferredType;
|
|
int nfuncs = 0;
|
|
int nmatches = 0;
|
|
Oid selectedType = InvalidOid;
|
|
Oid selectedFunc = InvalidOid;
|
|
CatCList *proclist;
|
|
int i;
|
|
|
|
/* Transform the raw expression tree */
|
|
node = transformExpr(pstate, clause, EXPR_KIND_WINDOW_FRAME_RANGE);
|
|
nodeType = exprType(node);
|
|
|
|
/*
|
|
* If there are multiple candidates, we'll prefer the one that exactly
|
|
* matches nodeType; or if nodeType is as yet unknown, prefer the one
|
|
* that exactly matches the sort column type. (The second rule is
|
|
* like what we do for "known_type operator unknown".)
|
|
*/
|
|
preferredType = (nodeType != UNKNOWNOID) ? nodeType : rangeopcintype;
|
|
|
|
/* Find the in_range support functions applicable to this case */
|
|
proclist = SearchSysCacheList2(AMPROCNUM,
|
|
ObjectIdGetDatum(rangeopfamily),
|
|
ObjectIdGetDatum(rangeopcintype));
|
|
for (i = 0; i < proclist->n_members; i++)
|
|
{
|
|
HeapTuple proctup = &proclist->members[i]->tuple;
|
|
Form_pg_amproc procform = (Form_pg_amproc) GETSTRUCT(proctup);
|
|
|
|
/* The search will find all support proc types; ignore others */
|
|
if (procform->amprocnum != BTINRANGE_PROC)
|
|
continue;
|
|
nfuncs++;
|
|
|
|
/* Ignore function if given value can't be coerced to that type */
|
|
if (!can_coerce_type(1, &nodeType, &procform->amprocrighttype,
|
|
COERCION_IMPLICIT))
|
|
continue;
|
|
nmatches++;
|
|
|
|
/* Remember preferred match, or any match if didn't find that */
|
|
if (selectedType != preferredType)
|
|
{
|
|
selectedType = procform->amprocrighttype;
|
|
selectedFunc = procform->amproc;
|
|
}
|
|
}
|
|
ReleaseCatCacheList(proclist);
|
|
|
|
/*
|
|
* Throw error if needed. It seems worth taking the trouble to
|
|
* distinguish "no support at all" from "you didn't match any
|
|
* available offset type".
|
|
*/
|
|
if (nfuncs == 0)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("RANGE with offset PRECEDING/FOLLOWING is not supported for column type %s",
|
|
format_type_be(rangeopcintype)),
|
|
parser_errposition(pstate, exprLocation(node))));
|
|
if (nmatches == 0)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("RANGE with offset PRECEDING/FOLLOWING is not supported for column type %s and offset type %s",
|
|
format_type_be(rangeopcintype),
|
|
format_type_be(nodeType)),
|
|
errhint("Cast the offset value to an appropriate type."),
|
|
parser_errposition(pstate, exprLocation(node))));
|
|
if (nmatches != 1 && selectedType != preferredType)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("RANGE with offset PRECEDING/FOLLOWING has multiple interpretations for column type %s and offset type %s",
|
|
format_type_be(rangeopcintype),
|
|
format_type_be(nodeType)),
|
|
errhint("Cast the offset value to the exact intended type."),
|
|
parser_errposition(pstate, exprLocation(node))));
|
|
|
|
/* OK, coerce the offset to the right type */
|
|
constructName = "RANGE";
|
|
node = coerce_to_specific_type(pstate, node,
|
|
selectedType, constructName);
|
|
*inRangeFunc = selectedFunc;
|
|
}
|
|
else if (frameOptions & FRAMEOPTION_GROUPS)
|
|
{
|
|
/* Transform the raw expression tree */
|
|
node = transformExpr(pstate, clause, EXPR_KIND_WINDOW_FRAME_GROUPS);
|
|
|
|
/*
|
|
* Like LIMIT clause, simply coerce to int8
|
|
*/
|
|
constructName = "GROUPS";
|
|
node = coerce_to_specific_type(pstate, node, INT8OID, constructName);
|
|
}
|
|
else
|
|
{
|
|
Assert(false);
|
|
node = NULL;
|
|
}
|
|
|
|
/* Disallow variables in frame offsets */
|
|
checkExprIsVarFree(pstate, node, constructName);
|
|
|
|
return node;
|
|
}
|