From 72bd38cc99a15da6f97373fae98027c908c398ea Mon Sep 17 00:00:00 2001 From: Alexander Korotkov Date: Mon, 8 Apr 2024 01:27:28 +0300 Subject: Transform OR clauses to ANY expression Replace (expr op C1) OR (expr op C2) ... with expr op ANY(ARRAY[C1, C2, ...]) on the preliminary stage of optimization when we are still working with the expression tree. Here Cn is a n-th constant expression, 'expr' is non-constant expression, 'op' is an operator which returns boolean result and has a commuter (for the case of reverse order of constant and non-constant parts of the expression, like 'Cn op expr'). Sometimes it can lead to not optimal plan. This is why there is a or_to_any_transform_limit GUC. It specifies a threshold value of length of arguments in an OR expression that triggers the OR-to-ANY transformation. Generally, more groupable OR arguments mean that transformation will be more likely to win than to lose. Discussion: https://postgr.es/m/567ED6CA.2040504%40sigaev.ru Author: Alena Rybakina Author: Andrey Lepikhov Reviewed-by: Peter Geoghegan Reviewed-by: Ranier Vilela Reviewed-by: Alexander Korotkov Reviewed-by: Robert Haas Reviewed-by: Jian He --- src/include/optimizer/optimizer.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'src/include/optimizer') diff --git a/src/include/optimizer/optimizer.h b/src/include/optimizer/optimizer.h index 7b63c5cf718..960dfb97a38 100644 --- a/src/include/optimizer/optimizer.h +++ b/src/include/optimizer/optimizer.h @@ -133,6 +133,8 @@ extern void extract_query_dependencies(Node *query, /* in prep/prepqual.c: */ +extern PGDLLIMPORT int or_to_any_transform_limit; + extern Node *negate_clause(Node *node); extern Expr *canonicalize_qual(Expr *qual, bool is_check); -- cgit v1.2.3