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Fix planner and rewriter to follow SQL semantics for tables that are

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mentioned in FROM but not elsewhere in the query: such tables should be
joined over anyway.  Aside from being more standards-compliant, this allows
removal of some very ugly hacks for COUNT(*) processing.  Also, allow
HAVING clause without aggregate functions, since SQL does.  Clean up
CREATE RULE statement-list syntax the same way Bruce just fixed the
main stmtmulti production.
CAUTION: addition of a field to RangeTblEntry nodes breaks stored rules;
you will have to initdb if you have any rules.
This commit is contained in:
Tom Lane
1999-10-07 04:23:24 +00:00
parent 4040fcfa78
commit 3eb1c82277
21 changed files with 408 additions and 390 deletions
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39
src/backend/optimizer/util/clauses.c
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@@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/optimizer/util/clauses.c,v 1.53 1999/10/02 04:37:52 tgl Exp $
* $Header: /cvsroot/pgsql/src/backend/optimizer/util/clauses.c,v 1.54 1999/10/07 04:23:08 tgl Exp $
*
* HISTORY
* AUTHOR DATE MAJOR EVENT
@@ -34,6 +34,11 @@
#include "utils/syscache.h"
/* note that pg_type.h hardwires size of bool as 1 ... duplicate it */
#define MAKEBOOLCONST(val,isnull) \
((Node *) makeConst(BOOLOID, 1, (Datum) (val), \
(isnull), true, false, false))
typedef struct {
List *groupClause;
List *targetList;
@@ -312,17 +317,20 @@ make_andclause(List *andclauses)
}
/*
* Sometimes (such as in the result of cnfify), we use lists of expression
* nodes with implicit AND semantics. These functions convert between an
* AND-semantics expression list and the ordinary representation of a
* boolean expression.
* Sometimes (such as in the result of canonicalize_qual or the input of
* ExecQual), we use lists of expression nodes with implicit AND semantics.
*
* These functions convert between an AND-semantics expression list and the
* ordinary representation of a boolean expression.
*
* Note that an empty list is considered equivalent to TRUE.
*/
Expr *
make_ands_explicit(List *andclauses)
{
if (andclauses == NIL)
return NULL;
else if (length(andclauses) == 1)
return (Expr *) MAKEBOOLCONST(true, false);
else if (lnext(andclauses) == NIL)
return (Expr *) lfirst(andclauses);
else
return make_andclause(andclauses);
@@ -331,10 +339,20 @@ make_ands_explicit(List *andclauses)
List *
make_ands_implicit(Expr *clause)
{
/*
* NB: because the parser sets the qual field to NULL in a query that
* has no WHERE clause, we must consider a NULL input clause as TRUE,
* even though one might more reasonably think it FALSE. Grumble.
* If this causes trouble, consider changing the parser's behavior.
*/
if (clause == NULL)
return NIL;
return NIL; /* NULL -> NIL list == TRUE */
else if (and_clause((Node *) clause))
return clause->args;
else if (IsA(clause, Const) &&
! ((Const *) clause)->constisnull &&
DatumGetInt32(((Const *) clause)->constvalue))
return NIL; /* constant TRUE input -> NIL list */
else
return lcons(clause, NIL);
}
@@ -808,11 +826,6 @@ eval_const_expressions(Node *node)
return eval_const_expressions_mutator(node, NULL);
}
/* note that pg_type.h hardwires size of bool as 1 ... duplicate it */
#define MAKEBOOLCONST(val,isnull) \
((Node *) makeConst(BOOLOID, 1, (Datum) (val), \
(isnull), true, false, false))
static Node *
eval_const_expressions_mutator (Node *node, void *context)
{