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Clean up the usage of canonicalize_qual(): in particular, be consistent

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about whether it is applied before or after eval_const_expressions().
I believe there were some corner cases where the system would fail to
recognize that a partial index is applicable because of the previous
inconsistency.  Store normal rather than 'implicit AND' representations
of constraints and index predicates in the catalogs.
initdb forced due to representation change of constraints/predicates.
This commit is contained in:
Tom Lane
2003-12-28 21:57:37 +00:00
parent d167fb1015
commit c607bd693f
13 changed files with 148 additions and 208 deletions
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33
src/backend/optimizer/plan/planner.c
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@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/plan/planner.c,v 1.162 2003/11/29 19:51:50 pgsql Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/plan/planner.c,v 1.163 2003/12/28 21:57:36 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -377,23 +377,13 @@ preprocess_expression(Query *parse, Node *expr, int kind)
expr = flatten_join_alias_vars(parse, expr);
/*
* Simplify constant expressions.
*
* Note that at this point quals have not yet been converted to
* implicit-AND form, so we can apply eval_const_expressions directly.
*/
expr = eval_const_expressions(expr);
/*
* If it's a qual or havingQual, canonicalize it, and convert it to
* implicit-AND format.
*
* XXX Is there any value in re-applying eval_const_expressions after
* canonicalize_qual?
* If it's a qual or havingQual, canonicalize it. It seems most useful
* to do this before applying eval_const_expressions, since the latter
* can optimize flattened AND/ORs better than unflattened ones.
*/
if (kind == EXPRKIND_QUAL)
{
expr = (Node *) canonicalize_qual((Expr *) expr, true);
expr = (Node *) canonicalize_qual((Expr *) expr);
#ifdef OPTIMIZER_DEBUG
printf("After canonicalize_qual()\n");
@ -401,6 +391,19 @@ preprocess_expression(Query *parse, Node *expr, int kind)
#endif
}
/*
* Simplify constant expressions.
*/
expr = eval_const_expressions(expr);
/*
* If it's a qual or havingQual, convert it to implicit-AND format.
* (We don't want to do this before eval_const_expressions, since the
* latter would be unable to simplify a top-level AND correctly.)
*/
if (kind == EXPRKIND_QUAL)
expr = (Node *) make_ands_implicit((Expr *) expr);
/* Expand SubLinks to SubPlans */
if (parse->hasSubLinks)
expr = SS_process_sublinks(expr, (kind == EXPRKIND_QUAL));