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Implement the IS DISTINCT FROM operator per SQL99.
Reused the Expr node to hold DISTINCT which strongly resembles the existing OP info. Define DISTINCT_EXPR which strongly resembles the existing OPER_EXPR opType, but with handling for NULLs required by SQL99. We have explicit support for single-element DISTINCT comparisons all the way through to the executor. But, multi-element DISTINCTs are handled by expanding into a comparison tree in gram.y as is done for other row comparisons. Per discussions, it might be desirable to move this into one or more purpose-built nodes to be handled in the backend. Define the optional ROW keyword and token per SQL99. This allows single-element row constructs, which were formerly disallowed due to shift/reduce conflicts with parenthesized a_expr clauses. Define the SQL99 TREAT() function. Currently, use as a synonym for CAST().
This commit is contained in:
Thomas G. Lockhart
parent
c7eea66c39
commit
68d9fbeb55
@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/executor/execQual.c,v 1.94 2002/06/20 20:29:27 momjian Exp $
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* $Header: /cvsroot/pgsql/src/backend/executor/execQual.c,v 1.95 2002/07/04 15:23:29 thomas Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -51,6 +51,8 @@ static Datum ExecEvalArrayRef(ArrayRef *arrayRef, ExprContext *econtext,
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static Datum ExecEvalVar(Var *variable, ExprContext *econtext, bool *isNull);
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static Datum ExecEvalOper(Expr *opClause, ExprContext *econtext,
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bool *isNull, ExprDoneCond *isDone);
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static Datum ExecEvalDistinct(Expr *opClause, ExprContext *econtext,
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bool *isNull, ExprDoneCond *isDone);
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static Datum ExecEvalFunc(Expr *funcClause, ExprContext *econtext,
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bool *isNull, ExprDoneCond *isDone);
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static ExprDoneCond ExecEvalFuncArgs(FunctionCallInfo fcinfo,
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@ -832,6 +834,7 @@ ExecMakeFunctionResult(FunctionCachePtr fcache,
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/* ----------------------------------------------------------------
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* ExecEvalOper
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* ExecEvalDistinct
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* ExecEvalFunc
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*
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* Evaluate the functional result of a list of arguments by calling the
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@ -878,6 +881,80 @@ ExecEvalOper(Expr *opClause,
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isNull, isDone);
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}
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/* ----------------------------------------------------------------
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* ExecEvalDistinct
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*
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* IS DISTINCT FROM must evaluate arguments to determine whether
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* they are NULL; if either is NULL then the result is already
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* known. If neither is NULL, then proceed to evaluate the
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* function. Note that this is *always* derived from the equals
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* operator, but since we've already evaluated the arguments
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* we can not simply reuse ExecEvalOper() or ExecEvalFunc().
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* ----------------------------------------------------------------
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*/
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static Datum
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ExecEvalDistinct(Expr *opClause,
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ExprContext *econtext,
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bool *isNull,
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ExprDoneCond *isDone)
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{
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bool result;
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FunctionCachePtr fcache;
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FunctionCallInfoData fcinfo;
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ExprDoneCond argDone;
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Oper *op;
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List *argList;
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/*
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* we extract the oid of the function associated with the op and then
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* pass the work onto ExecMakeFunctionResult which evaluates the
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* arguments and returns the result of calling the function on the
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* evaluated arguments.
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*/
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op = (Oper *) opClause->oper;
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argList = opClause->args;
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/*
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* get the fcache from the Oper node. If it is NULL, then initialize
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* it
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*/
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fcache = op->op_fcache;
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if (fcache == NULL)
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{
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fcache = init_fcache(op->opid, length(argList),
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econtext->ecxt_per_query_memory);
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op->op_fcache = fcache;
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}
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Assert(fcache->func.fn_retset == FALSE);
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/* Need to prep callinfo structure */
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MemSet(&fcinfo, 0, sizeof(fcinfo));
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fcinfo.flinfo = &(fcache->func);
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argDone = ExecEvalFuncArgs(&fcinfo, argList, econtext);
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Assert(fcinfo->nargs == 2);
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if (fcinfo.argnull[0] && fcinfo.argnull[1])
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{
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/* Both NULL? Then is not distinct... */
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result = FALSE;
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}
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else if (fcinfo.argnull[0] || fcinfo.argnull[1])
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{
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/* One is NULL? Then is distinct... */
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result = TRUE;
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}
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else
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{
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fcinfo.isnull = false;
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result = FunctionCallInvoke(&fcinfo);
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*isNull = fcinfo.isnull;
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result = (!DatumGetBool(result));
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}
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return BoolGetDatum(result);
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}
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/* ----------------------------------------------------------------
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* ExecEvalFunc
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* ----------------------------------------------------------------
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@ -1367,6 +1444,10 @@ ExecEvalExpr(Node *expression,
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case NOT_EXPR:
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retDatum = ExecEvalNot(expr, econtext, isNull);
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break;
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case DISTINCT_EXPR:
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retDatum = ExecEvalDistinct(expr, econtext,
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isNull, isDone);
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break;
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case SUBPLAN_EXPR:
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retDatum = ExecSubPlan((SubPlan *) expr->oper,
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expr->args, econtext,
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@ -5,7 +5,7 @@
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* Portions Copyright (c) 1996-2002, 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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* $Header: /cvsroot/pgsql/src/backend/nodes/outfuncs.c,v 1.160 2002/06/20 20:29:29 momjian Exp $
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* $Header: /cvsroot/pgsql/src/backend/nodes/outfuncs.c,v 1.161 2002/07/04 15:23:53 thomas Exp $
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*
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* NOTES
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* Every (plan) node in POSTGRES has an associated "out" routine which
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@ -719,6 +719,9 @@ _outExpr(StringInfo str, Expr *node)
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case OP_EXPR:
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opstr = "op";
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break;
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case DISTINCT_EXPR:
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opstr = "distinct";
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break;
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case FUNC_EXPR:
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opstr = "func";
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break;
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/nodes/readfuncs.c,v 1.123 2002/06/20 20:29:29 momjian Exp $
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* $Header: /cvsroot/pgsql/src/backend/nodes/readfuncs.c,v 1.124 2002/07/04 15:23:54 thomas Exp $
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*
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* NOTES
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* Most of the read functions for plan nodes are tested. (In fact, they
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@ -804,6 +804,8 @@ _readExpr(void)
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token = pg_strtok(&length); /* get opType */
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if (strncmp(token, "op", 2) == 0)
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local_node->opType = OP_EXPR;
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else if (strncmp(token, "distinct", 8) == 0)
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local_node->opType = DISTINCT_EXPR;
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else if (strncmp(token, "func", 4) == 0)
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local_node->opType = FUNC_EXPR;
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else if (strncmp(token, "or", 2) == 0)
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@ -42,7 +42,7 @@
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/optimizer/path/costsize.c,v 1.88 2002/06/26 21:58:56 momjian Exp $
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* $Header: /cvsroot/pgsql/src/backend/optimizer/path/costsize.c,v 1.89 2002/07/04 15:23:56 thomas Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -1092,6 +1092,7 @@ cost_qual_eval_walker(Node *node, Cost *total)
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switch (expr->opType)
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{
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case OP_EXPR:
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case DISTINCT_EXPR:
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case FUNC_EXPR:
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*total += cpu_operator_cost;
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break;
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/optimizer/util/clauses.c,v 1.101 2002/06/20 20:29:31 momjian Exp $
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* $Header: /cvsroot/pgsql/src/backend/optimizer/util/clauses.c,v 1.102 2002/07/04 15:23:58 thomas Exp $
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*
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* HISTORY
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* AUTHOR DATE MAJOR EVENT
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@ -71,6 +71,7 @@ make_clause(int type, Node *oper, List *args)
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expr->typeOid = BOOLOID;
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break;
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case OP_EXPR:
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case DISTINCT_EXPR:
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expr->typeOid = ((Oper *) oper)->opresulttype;
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break;
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case FUNC_EXPR:
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@ -107,7 +108,8 @@ is_opclause(Node *clause)
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{
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return (clause != NULL &&
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IsA(clause, Expr) &&
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((Expr *) clause)->opType == OP_EXPR);
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((((Expr *) clause)->opType == OP_EXPR) ||
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((Expr *) clause)->opType == DISTINCT_EXPR));
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}
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/*
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@ -458,7 +460,7 @@ pull_agg_clause_walker(Node *node, List **listptr)
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/*
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* expression_returns_set
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* Test whethe an expression returns a set result.
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* Test whether an expression returns a set result.
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*
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* Because we use expression_tree_walker(), this can also be applied to
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* whole targetlists; it'll produce TRUE if any one of the tlist items
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@ -482,6 +484,7 @@ expression_returns_set_walker(Node *node, void *context)
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switch (expr->opType)
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{
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case OP_EXPR:
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case DISTINCT_EXPR:
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if (((Oper *) expr->oper)->opretset)
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return true;
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/* else fall through to check args */
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@ -757,6 +760,7 @@ contain_mutable_functions_walker(Node *node, void *context)
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switch (expr->opType)
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{
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case OP_EXPR:
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case DISTINCT_EXPR:
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if (op_volatile(((Oper *) expr->oper)->opno) != PROVOLATILE_IMMUTABLE)
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return true;
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break;
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@ -806,6 +810,7 @@ contain_volatile_functions_walker(Node *node, void *context)
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switch (expr->opType)
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{
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case OP_EXPR:
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case DISTINCT_EXPR:
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if (op_volatile(((Oper *) expr->oper)->opno) == PROVOLATILE_VOLATILE)
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return true;
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break;
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@ -1138,7 +1143,7 @@ eval_const_expressions_mutator(Node *node, void *context)
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* expression_tree_mutator directly rather than recursing to self.
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*/
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args = (List *) expression_tree_mutator((Node *) expr->args,
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eval_const_expressions_mutator,
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eval_const_expressions_mutator,
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(void *) context);
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switch (expr->opType)
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@ -1159,6 +1164,97 @@ eval_const_expressions_mutator(Node *node, void *context)
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* args
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*/
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break;
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case DISTINCT_EXPR:
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{
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List *arg;
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bool has_null_input = false;
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bool all_null_input = true;
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bool has_nonconst_input = false;
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/*
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* Check for constant inputs and especially constant-NULL inputs.
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*/
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Assert(length(args) == 2);
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foreach(arg, args)
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{
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if (IsA(lfirst(arg), Const))
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{
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has_null_input |= ((Const *) lfirst(arg))->constisnull;
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all_null_input &= ((Const *) lfirst(arg))->constisnull;
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}
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else
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{
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has_nonconst_input = true;
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}
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}
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/* all nulls? then not distinct */
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if (all_null_input)
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return MAKEBOOLCONST(false, false);
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/* one null? then distinct */
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if (has_null_input)
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return MAKEBOOLCONST(true, false);
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/* all constants? then optimize this out */
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if (!has_nonconst_input)
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{
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Oid result_typeid;
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int16 resultTypLen;
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bool resultTypByVal;
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ExprContext *econtext;
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Datum const_val;
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bool const_is_null;
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Oper *oper = (Oper *) expr->oper;
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replace_opid(oper); /* OK to scribble on input to this extent */
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result_typeid = oper->opresulttype;
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/*
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* OK, looks like we can simplify this operator/function.
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*
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* We use the executor's routine ExecEvalExpr() to avoid duplication of
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* code and ensure we get the same result as the executor would get.
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*
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* Build a new Expr node containing the already-simplified arguments. The
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* only other setup needed here is the replace_opid() that we already
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* did for the OP_EXPR case.
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*/
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newexpr = makeNode(Expr);
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newexpr->typeOid = expr->typeOid;
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newexpr->opType = expr->opType;
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newexpr->oper = expr->oper;
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newexpr->args = args;
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/* Get info needed about result datatype */
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get_typlenbyval(result_typeid, &resultTypLen, &resultTypByVal);
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/*
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* It is OK to pass a dummy econtext because none of the
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* ExecEvalExpr() code used in this situation will use econtext. That
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* might seem fortuitous, but it's not so unreasonable --- a constant
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* expression does not depend on context, by definition, n'est ce pas?
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*/
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econtext = MakeExprContext(NULL, CurrentMemoryContext);
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const_val = ExecEvalExprSwitchContext((Node *) newexpr, econtext,
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&const_is_null, NULL);
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/* Must copy result out of sub-context used by expression eval */
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if (!const_is_null)
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const_val = datumCopy(const_val, resultTypByVal, resultTypLen);
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FreeExprContext(econtext);
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pfree(newexpr);
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/*
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* Make the constant result node.
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*/
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return (Node *) makeConst(result_typeid, resultTypLen,
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const_val, const_is_null,
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resultTypByVal, false, false);
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}
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break;
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}
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case OR_EXPR:
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{
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@ -11,7 +11,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.335 2002/07/01 15:27:55 tgl Exp $
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* $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.336 2002/07/04 15:23:59 thomas Exp $
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*
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* HISTORY
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* AUTHOR DATE MAJOR EVENT
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@ -90,7 +90,11 @@ static Node *makeIntConst(int val);
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static Node *makeFloatConst(char *str);
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static Node *makeAConst(Value *v);
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static Node *makeRowExpr(List *opr, List *largs, List *rargs);
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static Node *makeDistinctExpr(List *largs, List *rargs);
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static Node *makeRowNullTest(NullTestType test, List *args);
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static DefElem *makeDefElem(char *name, Node *arg);
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static A_Const *makeBoolConst(bool state);
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static FuncCall *makeOverlaps(List *largs, List *rargs);
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static SelectStmt *findLeftmostSelect(SelectStmt *node);
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static void insertSelectOptions(SelectStmt *stmt,
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List *sortClause, List *forUpdate,
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@ -265,10 +269,9 @@ static void doNegateFloat(Value *v);
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%type <node> columnDef
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%type <defelt> def_elem
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%type <node> def_arg, columnElem, where_clause, insert_column_item,
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a_expr, b_expr, c_expr, AexprConst,
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a_expr, b_expr, c_expr, r_expr, AexprConst,
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in_expr, having_clause, func_table
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%type <list> row_descriptor, row_list, in_expr_nodes
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%type <node> row_expr
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%type <list> row, row_descriptor, row_list, in_expr_nodes
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%type <node> case_expr, case_arg, when_clause, case_default
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%type <list> when_clause_list
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%type <ival> sub_type
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@ -386,7 +389,7 @@ static void doNegateFloat(Value *v);
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SYSID,
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TABLE, TEMP, TEMPLATE, TEMPORARY, THEN, TIME, TIMESTAMP,
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TO, TOAST, TRAILING, TRANSACTION, TRIGGER, TRIM, TRUE_P,
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TO, TOAST, TRAILING, TRANSACTION, TREAT, TRIGGER, TRIM, TRUE_P,
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TRUNCATE, TRUSTED, TYPE_P,
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UNENCRYPTED, UNION, UNIQUE, UNKNOWN, UNLISTEN, UNTIL,
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@ -426,7 +429,7 @@ static void doNegateFloat(Value *v);
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%nonassoc LIKE ILIKE SIMILAR
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%nonassoc ESCAPE
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%nonassoc OVERLAPS
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%nonassoc BETWEEN
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%nonassoc BETWEEN DISTINCT
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%nonassoc IN_P
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%left POSTFIXOP /* dummy for postfix Op rules */
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%left Op OPERATOR /* multi-character ops and user-defined operators */
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@ -5072,84 +5075,115 @@ opt_interval:
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/* Expressions using row descriptors
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* Define row_descriptor to allow yacc to break the reduce/reduce conflict
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* with singleton expressions.
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* with singleton expressions. Use SQL99's ROW keyword to allow rows of
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* one element.
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*/
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row_expr: '(' row_descriptor ')' IN_P select_with_parens
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r_expr: row IN_P select_with_parens
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{
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SubLink *n = makeNode(SubLink);
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n->lefthand = $2;
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n->lefthand = $1;
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n->oper = (List *) makeSimpleA_Expr(OP, "=", NULL, NULL);
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n->useor = FALSE;
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n->subLinkType = ANY_SUBLINK;
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n->subselect = $5;
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n->subselect = $3;
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$$ = (Node *)n;
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}
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| '(' row_descriptor ')' NOT IN_P select_with_parens
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| row NOT IN_P select_with_parens
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{
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SubLink *n = makeNode(SubLink);
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n->lefthand = $2;
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n->lefthand = $1;
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n->oper = (List *) makeSimpleA_Expr(OP, "<>", NULL, NULL);
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n->useor = TRUE;
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n->subLinkType = ALL_SUBLINK;
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n->subselect = $6;
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n->subselect = $4;
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$$ = (Node *)n;
|
||||
}
|
||||
| '(' row_descriptor ')' qual_all_Op sub_type select_with_parens
|
||||
| row qual_all_Op sub_type select_with_parens
|
||||
%prec Op
|
||||
{
|
||||
SubLink *n = makeNode(SubLink);
|
||||
n->lefthand = $2;
|
||||
n->oper = (List *) makeA_Expr(OP, $4, NULL, NULL);
|
||||
if (strcmp(strVal(llast($4)), "<>") == 0)
|
||||
n->lefthand = $1;
|
||||
n->oper = (List *) makeA_Expr(OP, $2, NULL, NULL);
|
||||
if (strcmp(strVal(llast($2)), "<>") == 0)
|
||||
n->useor = TRUE;
|
||||
else
|
||||
n->useor = FALSE;
|
||||
n->subLinkType = $5;
|
||||
n->subselect = $6;
|
||||
n->subLinkType = $3;
|
||||
n->subselect = $4;
|
||||
$$ = (Node *)n;
|
||||
}
|
||||
| '(' row_descriptor ')' qual_all_Op select_with_parens
|
||||
| row qual_all_Op select_with_parens
|
||||
%prec Op
|
||||
{
|
||||
SubLink *n = makeNode(SubLink);
|
||||
n->lefthand = $2;
|
||||
n->oper = (List *) makeA_Expr(OP, $4, NULL, NULL);
|
||||
if (strcmp(strVal(llast($4)), "<>") == 0)
|
||||
n->lefthand = $1;
|
||||
n->oper = (List *) makeA_Expr(OP, $2, NULL, NULL);
|
||||
if (strcmp(strVal(llast($2)), "<>") == 0)
|
||||
n->useor = TRUE;
|
||||
else
|
||||
n->useor = FALSE;
|
||||
n->subLinkType = MULTIEXPR_SUBLINK;
|
||||
n->subselect = $5;
|
||||
n->subselect = $3;
|
||||
$$ = (Node *)n;
|
||||
}
|
||||
| '(' row_descriptor ')' qual_all_Op '(' row_descriptor ')'
|
||||
| row qual_all_Op row
|
||||
%prec Op
|
||||
{
|
||||
$$ = makeRowExpr($4, $2, $6);
|
||||
$$ = makeRowExpr($2, $1, $3);
|
||||
}
|
||||
| '(' row_descriptor ')' OVERLAPS '(' row_descriptor ')'
|
||||
| row IS NULL_P
|
||||
{
|
||||
FuncCall *n = makeNode(FuncCall);
|
||||
List *largs = $2;
|
||||
List *rargs = $6;
|
||||
n->funcname = SystemFuncName("overlaps");
|
||||
if (length(largs) == 1)
|
||||
largs = lappend(largs, $2);
|
||||
else if (length(largs) != 2)
|
||||
elog(ERROR, "Wrong number of parameters"
|
||||
" on left side of OVERLAPS expression");
|
||||
if (length(rargs) == 1)
|
||||
rargs = lappend(rargs, $6);
|
||||
else if (length(rargs) != 2)
|
||||
elog(ERROR, "Wrong number of parameters"
|
||||
" on right side of OVERLAPS expression");
|
||||
n->args = nconc(largs, rargs);
|
||||
n->agg_star = FALSE;
|
||||
n->agg_distinct = FALSE;
|
||||
$$ = (Node *)n;
|
||||
$$ = makeRowNullTest(IS_NULL, $1);
|
||||
}
|
||||
| row IS NOT NULL_P
|
||||
{
|
||||
$$ = makeRowNullTest(IS_NOT_NULL, $1);
|
||||
}
|
||||
| row OVERLAPS row
|
||||
{
|
||||
$$ = (Node *)makeOverlaps($1, $3);
|
||||
}
|
||||
| row IS DISTINCT FROM row
|
||||
{
|
||||
/* IS DISTINCT FROM has the following rules for non-array types:
|
||||
* a) the row lengths must be equal
|
||||
* b) if both rows are zero-length, then they are not distinct
|
||||
* c) if any element is distinct, the rows are distinct
|
||||
* The rules for an element being distinct:
|
||||
* a) if the elements are both NULL, then they are not distinct
|
||||
* b) if the elements compare to be equal, then they are not distinct
|
||||
* c) otherwise, they are distinct
|
||||
*/
|
||||
List *largs = $1;
|
||||
List *rargs = $5;
|
||||
/* lengths don't match? then complain */
|
||||
if (length(largs) != length(rargs))
|
||||
{
|
||||
elog(ERROR, "Unequal number of entries in row expression");
|
||||
}
|
||||
/* both are zero-length rows? then they are not distinct */
|
||||
else if (length(largs) <= 0)
|
||||
{
|
||||
$$ = (Node *)makeBoolConst(FALSE);
|
||||
}
|
||||
/* otherwise, we need to compare each element */
|
||||
else
|
||||
{
|
||||
$$ = (Node *)makeDistinctExpr(largs, rargs);
|
||||
}
|
||||
}
|
||||
;
|
||||
|
||||
/* Explicit row production.
|
||||
* SQL99 allows an optional ROW keyword, so we can now do single-element productions
|
||||
* without conflicting with the parenthesized a_expr production.
|
||||
*/
|
||||
row: ROW '(' row_descriptor ')' { $$ = $3; }
|
||||
| ROW '(' a_expr ')' { $$ = makeList1($3); }
|
||||
| ROW '(' ')' { $$ = NULL; }
|
||||
| '(' row_descriptor ')' { $$ = $2; }
|
||||
;
|
||||
|
||||
row_descriptor:
|
||||
row_list ',' a_expr { $$ = lappend($1, $3); }
|
||||
;
|
||||
@ -5356,8 +5390,6 @@ a_expr: c_expr { $$ = $1; }
|
||||
* Allow two SQL extensions
|
||||
* a ISNULL
|
||||
* a NOTNULL
|
||||
* NOTE: this is not yet fully SQL-compatible, since SQL92
|
||||
* allows a row constructor as argument, not just a scalar.
|
||||
*/
|
||||
| a_expr ISNULL
|
||||
{
|
||||
@ -5387,15 +5419,6 @@ a_expr: c_expr { $$ = $1; }
|
||||
n->nulltesttype = IS_NOT_NULL;
|
||||
$$ = (Node *)n;
|
||||
}
|
||||
/* IS TRUE, IS FALSE, etc used to be function calls
|
||||
* but let's make them expressions to allow the optimizer
|
||||
* a chance to eliminate them if a_expr is a constant string.
|
||||
* - thomas 1997-12-22
|
||||
*
|
||||
* Created BooleanTest Node type, and changed handling
|
||||
* for NULL inputs
|
||||
* - jec 2001-06-18
|
||||
*/
|
||||
| a_expr IS TRUE_P
|
||||
{
|
||||
BooleanTest *b = makeNode(BooleanTest);
|
||||
@ -5438,6 +5461,8 @@ a_expr: c_expr { $$ = $1; }
|
||||
b->booltesttype = IS_NOT_UNKNOWN;
|
||||
$$ = (Node *)b;
|
||||
}
|
||||
| a_expr IS DISTINCT FROM a_expr %prec DISTINCT
|
||||
{ $$ = (Node *) makeSimpleA_Expr(DISTINCT, "=", $1, $5); }
|
||||
| a_expr BETWEEN b_expr AND b_expr %prec BETWEEN
|
||||
{
|
||||
$$ = (Node *) makeA_Expr(AND, NIL,
|
||||
@ -5457,8 +5482,7 @@ a_expr: c_expr { $$ = $1; }
|
||||
{
|
||||
SubLink *n = (SubLink *)$3;
|
||||
n->lefthand = makeList1($1);
|
||||
n->oper = (List *) makeSimpleA_Expr(OP, "=",
|
||||
NULL, NULL);
|
||||
n->oper = (List *) makeSimpleA_Expr(OP, "=", NULL, NULL);
|
||||
n->useor = FALSE;
|
||||
n->subLinkType = ANY_SUBLINK;
|
||||
$$ = (Node *)n;
|
||||
@ -5470,8 +5494,7 @@ a_expr: c_expr { $$ = $1; }
|
||||
foreach(l, (List *) $3)
|
||||
{
|
||||
Node *cmp;
|
||||
cmp = (Node *) makeSimpleA_Expr(OP, "=",
|
||||
$1, lfirst(l));
|
||||
cmp = (Node *) makeSimpleA_Expr(OP, "=", $1, lfirst(l));
|
||||
if (n == NULL)
|
||||
n = cmp;
|
||||
else
|
||||
@ -5487,8 +5510,7 @@ a_expr: c_expr { $$ = $1; }
|
||||
{
|
||||
SubLink *n = (SubLink *)$4;
|
||||
n->lefthand = makeList1($1);
|
||||
n->oper = (List *) makeSimpleA_Expr(OP, "<>",
|
||||
NULL, NULL);
|
||||
n->oper = (List *) makeSimpleA_Expr(OP, "<>", NULL, NULL);
|
||||
n->useor = FALSE;
|
||||
n->subLinkType = ALL_SUBLINK;
|
||||
$$ = (Node *)n;
|
||||
@ -5500,8 +5522,7 @@ a_expr: c_expr { $$ = $1; }
|
||||
foreach(l, (List *) $4)
|
||||
{
|
||||
Node *cmp;
|
||||
cmp = (Node *) makeSimpleA_Expr(OP, "<>",
|
||||
$1, lfirst(l));
|
||||
cmp = (Node *) makeSimpleA_Expr(OP, "<>", $1, lfirst(l));
|
||||
if (n == NULL)
|
||||
n = cmp;
|
||||
else
|
||||
@ -5520,7 +5541,7 @@ a_expr: c_expr { $$ = $1; }
|
||||
n->subselect = $4;
|
||||
$$ = (Node *)n;
|
||||
}
|
||||
| row_expr
|
||||
| r_expr
|
||||
{ $$ = $1; }
|
||||
;
|
||||
|
||||
@ -5573,6 +5594,8 @@ b_expr: c_expr
|
||||
{ $$ = (Node *) makeA_Expr(OP, $1, NULL, $2); }
|
||||
| b_expr qual_Op %prec POSTFIXOP
|
||||
{ $$ = (Node *) makeA_Expr(OP, $2, $1, NULL); }
|
||||
| b_expr IS DISTINCT FROM b_expr %prec Op
|
||||
{ $$ = (Node *) makeSimpleA_Expr(DISTINCT, "=", $1, $5); }
|
||||
;
|
||||
|
||||
/*
|
||||
@ -5606,8 +5629,6 @@ c_expr: columnref { $$ = (Node *) $1; }
|
||||
n->indirection = $5;
|
||||
$$ = (Node *)n;
|
||||
}
|
||||
| CAST '(' a_expr AS Typename ')'
|
||||
{ $$ = makeTypeCast($3, $5); }
|
||||
| case_expr
|
||||
{ $$ = $1; }
|
||||
| func_name '(' ')'
|
||||
@ -5908,6 +5929,8 @@ c_expr: columnref { $$ = (Node *) $1; }
|
||||
n->agg_distinct = FALSE;
|
||||
$$ = (Node *)n;
|
||||
}
|
||||
| CAST '(' a_expr AS Typename ')'
|
||||
{ $$ = makeTypeCast($3, $5); }
|
||||
| EXTRACT '(' extract_list ')'
|
||||
{
|
||||
FuncCall *n = makeNode(FuncCall);
|
||||
@ -5953,6 +5976,22 @@ c_expr: columnref { $$ = (Node *) $1; }
|
||||
n->agg_distinct = FALSE;
|
||||
$$ = (Node *)n;
|
||||
}
|
||||
| TREAT '(' a_expr AS Typename ')'
|
||||
{
|
||||
/* TREAT(expr AS target) converts expr of a particular type to target,
|
||||
* which is defined to be a subtype of the original expression.
|
||||
* In SQL99, this is intended for use with structured UDTs,
|
||||
* but let's make this a generally useful form allowing stronger
|
||||
* coersions than are handled by implicit casting.
|
||||
*/
|
||||
FuncCall *n = makeNode(FuncCall);
|
||||
/* Convert SystemTypeName() to SystemFuncName() even though
|
||||
* at the moment they result in the same thing.
|
||||
*/
|
||||
n->funcname = SystemFuncName(((Value *)llast($5->names))->val.str);
|
||||
n->args = makeList1($3);
|
||||
$$ = (Node *)n;
|
||||
}
|
||||
| TRIM '(' BOTH trim_list ')'
|
||||
{
|
||||
/* various trim expressions are defined in SQL92
|
||||
@ -6505,19 +6544,11 @@ AexprConst: Iconst
|
||||
}
|
||||
| TRUE_P
|
||||
{
|
||||
A_Const *n = makeNode(A_Const);
|
||||
n->val.type = T_String;
|
||||
n->val.val.str = "t";
|
||||
n->typename = SystemTypeName("bool");
|
||||
$$ = (Node *)n;
|
||||
$$ = (Node *)makeBoolConst(TRUE);
|
||||
}
|
||||
| FALSE_P
|
||||
{
|
||||
A_Const *n = makeNode(A_Const);
|
||||
n->val.type = T_String;
|
||||
n->val.val.str = "f";
|
||||
n->typename = SystemTypeName("bool");
|
||||
$$ = (Node *)n;
|
||||
$$ = (Node *)makeBoolConst(FALSE);
|
||||
}
|
||||
| NULL_P
|
||||
{
|
||||
@ -6707,7 +6738,6 @@ unreserved_keyword:
|
||||
| RETURNS
|
||||
| REVOKE
|
||||
| ROLLBACK
|
||||
| ROW
|
||||
| RULE
|
||||
| SCHEMA
|
||||
| SCROLL
|
||||
@ -6792,6 +6822,7 @@ col_name_keyword:
|
||||
| OVERLAY
|
||||
| POSITION
|
||||
| REAL
|
||||
| ROW
|
||||
| SETOF
|
||||
| SMALLINT
|
||||
| SUBSTRING
|
||||
@ -6903,6 +6934,7 @@ reserved_keyword:
|
||||
| THEN
|
||||
| TO
|
||||
| TRAILING
|
||||
| TREAT
|
||||
| TRUE_P
|
||||
| UNION
|
||||
| UNIQUE
|
||||
@ -7028,6 +7060,19 @@ makeDefElem(char *name, Node *arg)
|
||||
return f;
|
||||
}
|
||||
|
||||
/* makeBoolConst()
|
||||
* Create an A_Const node and initialize to a boolean constant.
|
||||
*/
|
||||
static A_Const *
|
||||
makeBoolConst(bool state)
|
||||
{
|
||||
A_Const *n = makeNode(A_Const);
|
||||
n->val.type = T_String;
|
||||
n->val.val.str = (state? "t": "f");
|
||||
n->typename = SystemTypeName("bool");
|
||||
return n;
|
||||
}
|
||||
|
||||
/* makeRowExpr()
|
||||
* Generate separate operator nodes for a single row descriptor expression.
|
||||
* Perhaps this should go deeper in the parser someday...
|
||||
@ -7082,8 +7127,90 @@ makeRowExpr(List *opr, List *largs, List *rargs)
|
||||
return expr;
|
||||
}
|
||||
|
||||
/* makeDistinctExpr()
|
||||
* Generate separate operator nodes for a single row descriptor expression.
|
||||
* Same comments as for makeRowExpr().
|
||||
*/
|
||||
static Node *
|
||||
makeDistinctExpr(List *largs, List *rargs)
|
||||
{
|
||||
Node *expr = NULL;
|
||||
Node *larg, *rarg;
|
||||
|
||||
if (length(largs) != length(rargs))
|
||||
elog(ERROR, "Unequal number of entries in row expression");
|
||||
|
||||
if (lnext(largs) != NIL)
|
||||
expr = makeDistinctExpr(lnext(largs), lnext(rargs));
|
||||
|
||||
larg = lfirst(largs);
|
||||
rarg = lfirst(rargs);
|
||||
|
||||
if (expr == NULL)
|
||||
expr = (Node *) makeSimpleA_Expr(DISTINCT, "=", larg, rarg);
|
||||
else
|
||||
expr = (Node *) makeA_Expr(OR, NIL, expr,
|
||||
(Node *) makeSimpleA_Expr(DISTINCT, "=",
|
||||
larg, rarg));
|
||||
|
||||
return expr;
|
||||
}
|
||||
|
||||
/* makeRowNullTest()
|
||||
* Generate separate operator nodes for a single row descriptor test.
|
||||
*/
|
||||
static Node *
|
||||
makeRowNullTest(NullTestType test, List *args)
|
||||
{
|
||||
Node *expr = NULL;
|
||||
Node *arg;
|
||||
NullTest *n;
|
||||
|
||||
if (lnext(args) != NIL)
|
||||
expr = makeRowNullTest(test, lnext(args));
|
||||
|
||||
arg = lfirst(args);
|
||||
|
||||
n = makeNode(NullTest);
|
||||
n->arg = arg;
|
||||
n->nulltesttype = test;
|
||||
|
||||
if (expr == NULL)
|
||||
expr = (Node *)n;
|
||||
else if (test == IS_NOT_NULL)
|
||||
expr = (Node *) makeA_Expr(OR, NIL, expr, (Node *)n);
|
||||
else
|
||||
expr = (Node *) makeA_Expr(AND, NIL, expr, (Node *)n);
|
||||
|
||||
return expr;
|
||||
}
|
||||
|
||||
/* makeOverlaps()
|
||||
* Create and populate a FuncCall node to support the OVERLAPS operator.
|
||||
*/
|
||||
static FuncCall *
|
||||
makeOverlaps(List *largs, List *rargs)
|
||||
{
|
||||
FuncCall *n = makeNode(FuncCall);
|
||||
n->funcname = SystemFuncName("overlaps");
|
||||
if (length(largs) == 1)
|
||||
largs = lappend(largs, largs);
|
||||
else if (length(largs) != 2)
|
||||
elog(ERROR, "Wrong number of parameters"
|
||||
" on left side of OVERLAPS expression");
|
||||
if (length(rargs) == 1)
|
||||
rargs = lappend(rargs, rargs);
|
||||
else if (length(rargs) != 2)
|
||||
elog(ERROR, "Wrong number of parameters"
|
||||
" on right side of OVERLAPS expression");
|
||||
n->args = nconc(largs, rargs);
|
||||
n->agg_star = FALSE;
|
||||
n->agg_distinct = FALSE;
|
||||
return n;
|
||||
}
|
||||
|
||||
/* findLeftmostSelect()
|
||||
* Find the leftmost component SelectStmt in a set-operation parsetree.
|
||||
* Find the leftmost component SelectStmt in a set-operation parsetree.
|
||||
*/
|
||||
static SelectStmt *
|
||||
findLeftmostSelect(SelectStmt *node)
|
||||
@ -7095,7 +7222,7 @@ findLeftmostSelect(SelectStmt *node)
|
||||
}
|
||||
|
||||
/* insertSelectOptions()
|
||||
* Insert ORDER BY, etc into an already-constructed SelectStmt.
|
||||
* Insert ORDER BY, etc into an already-constructed SelectStmt.
|
||||
*
|
||||
* This routine is just to avoid duplicating code in SelectStmt productions.
|
||||
*/
|
||||
@ -7147,7 +7274,7 @@ makeSetOp(SetOperation op, bool all, Node *larg, Node *rarg)
|
||||
}
|
||||
|
||||
/* SystemFuncName()
|
||||
* Build a properly-qualified reference to a built-in function.
|
||||
* Build a properly-qualified reference to a built-in function.
|
||||
*/
|
||||
List *
|
||||
SystemFuncName(char *name)
|
||||
@ -7156,7 +7283,7 @@ SystemFuncName(char *name)
|
||||
}
|
||||
|
||||
/* SystemTypeName()
|
||||
* Build a properly-qualified reference to a built-in type.
|
||||
* Build a properly-qualified reference to a built-in type.
|
||||
*
|
||||
* typmod is defaulted, but may be changed afterwards by caller.
|
||||
*/
|
||||
@ -7170,7 +7297,7 @@ SystemTypeName(char *name)
|
||||
return n;
|
||||
}
|
||||
|
||||
/*
|
||||
/* parser_init()
|
||||
* Initialize to parse one query string
|
||||
*/
|
||||
void
|
||||
@ -7185,7 +7312,7 @@ parser_init(Oid *typev, int nargs)
|
||||
pfunc_num_args = nargs;
|
||||
}
|
||||
|
||||
/*
|
||||
/* param_type()
|
||||
* Fetch a parameter type previously passed to parser_init
|
||||
*/
|
||||
Oid
|
||||
@ -7196,7 +7323,7 @@ param_type(int t)
|
||||
return param_type_info[t - 1];
|
||||
}
|
||||
|
||||
/*
|
||||
/* exprIsNullConstant()
|
||||
* Test whether an a_expr is a plain NULL constant or not.
|
||||
*/
|
||||
bool
|
||||
@ -7213,8 +7340,8 @@ exprIsNullConstant(Node *arg)
|
||||
return FALSE;
|
||||
}
|
||||
|
||||
/*
|
||||
* doNegate --- handle negation of a numeric constant.
|
||||
/* doNegate()
|
||||
* Handle negation of a numeric constant.
|
||||
*
|
||||
* Formerly, we did this here because the optimizer couldn't cope with
|
||||
* indexquals that looked like "var = -4" --- it wants "var = const"
|
||||
|
||||
@ -8,7 +8,7 @@
|
||||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $Header: /cvsroot/pgsql/src/backend/parser/keywords.c,v 1.117 2002/06/22 02:04:45 thomas Exp $
|
||||
* $Header: /cvsroot/pgsql/src/backend/parser/keywords.c,v 1.118 2002/07/04 15:24:01 thomas Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -283,6 +283,7 @@ static const ScanKeyword ScanKeywords[] = {
|
||||
{"toast", TOAST},
|
||||
{"trailing", TRAILING},
|
||||
{"transaction", TRANSACTION},
|
||||
{"treat", TREAT},
|
||||
{"trigger", TRIGGER},
|
||||
{"trim", TRIM},
|
||||
{"true", TRUE_P},
|
||||
|
||||
@ -8,7 +8,7 @@
|
||||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $Header: /cvsroot/pgsql/src/backend/parser/parse_expr.c,v 1.119 2002/06/20 20:29:32 momjian Exp $
|
||||
* $Header: /cvsroot/pgsql/src/backend/parser/parse_expr.c,v 1.120 2002/07/04 15:24:01 thomas Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -271,6 +271,17 @@ transformExpr(ParseState *pstate, Node *expr)
|
||||
result = (Node *) expr;
|
||||
}
|
||||
break;
|
||||
case DISTINCT:
|
||||
{
|
||||
Node *lexpr = transformExpr(pstate,
|
||||
a->lexpr);
|
||||
Node *rexpr = transformExpr(pstate,
|
||||
a->rexpr);
|
||||
result = (Node *) make_op(a->name,
|
||||
lexpr,
|
||||
rexpr);
|
||||
((Expr *)result)->opType = DISTINCT_EXPR;
|
||||
}
|
||||
}
|
||||
break;
|
||||
}
|
||||
|
||||
@ -3,7 +3,7 @@
|
||||
* back to source text
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $Header: /cvsroot/pgsql/src/backend/utils/adt/ruleutils.c,v 1.108 2002/06/13 03:40:49 tgl Exp $
|
||||
* $Header: /cvsroot/pgsql/src/backend/utils/adt/ruleutils.c,v 1.109 2002/07/04 15:24:07 thomas Exp $
|
||||
*
|
||||
* This software is copyrighted by Jan Wieck - Hamburg.
|
||||
*
|
||||
@ -1626,6 +1626,21 @@ get_rule_expr(Node *node, deparse_context *context)
|
||||
get_oper_expr(expr, context);
|
||||
break;
|
||||
|
||||
case DISTINCT_EXPR:
|
||||
appendStringInfoChar(buf, '(');
|
||||
Assert(length(args) == 2);
|
||||
{
|
||||
/* binary operator */
|
||||
Node *arg1 = (Node *) lfirst(args);
|
||||
Node *arg2 = (Node *) lsecond(args);
|
||||
|
||||
get_rule_expr(arg1, context);
|
||||
appendStringInfo(buf, " IS DISTINCT FROM ");
|
||||
get_rule_expr(arg2, context);
|
||||
}
|
||||
appendStringInfoChar(buf, ')');
|
||||
break;
|
||||
|
||||
case FUNC_EXPR:
|
||||
get_func_expr(expr, context);
|
||||
break;
|
||||
|
||||
@ -10,7 +10,7 @@
|
||||
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $Id: primnodes.h,v 1.64 2002/06/20 20:29:51 momjian Exp $
|
||||
* $Id: primnodes.h,v 1.65 2002/07/04 15:24:11 thomas Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -144,7 +144,8 @@ typedef struct RangeVar
|
||||
*/
|
||||
typedef enum OpType
|
||||
{
|
||||
OP_EXPR, FUNC_EXPR, OR_EXPR, AND_EXPR, NOT_EXPR, SUBPLAN_EXPR
|
||||
OP_EXPR, DISTINCT_EXPR, FUNC_EXPR,
|
||||
OR_EXPR, AND_EXPR, NOT_EXPR, SUBPLAN_EXPR
|
||||
} OpType;
|
||||
|
||||
typedef struct Expr
|
||||
|
||||
Loading…
Reference in New Issue
Block a user