From 8d96a06d43378ee8e509eb0d5d5dc3958fe7980f Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Wed, 3 Jan 2007 22:39:57 +0000 Subject: Fix regex_fixed_prefix() to cope reasonably well with regex patterns of the form '^(foo)$'. Before, these could never be optimized into indexscans. The recent changes to make psql and pg_dump generate such patterns (for \d commands and -t and related switches, respectively) therefore represented a big performance hit for people with large pg_class catalogs, as seen in recent gripe from Erik Jones. While at it, be more paranoid about case-sensitivity checking in multibyte encodings, and fix some other corner cases in which a regex might be interpreted too liberally. --- src/backend/utils/adt/regexp.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'src/backend/utils/adt/regexp.c') diff --git a/src/backend/utils/adt/regexp.c b/src/backend/utils/adt/regexp.c index cfd946e6303..37a82eed4fd 100644 --- a/src/backend/utils/adt/regexp.c +++ b/src/backend/utils/adt/regexp.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/utils/adt/regexp.c,v 1.49.4.3 2006/04/13 18:01:53 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/utils/adt/regexp.c,v 1.49.4.4 2007/01/03 22:39:56 tgl Exp $ * * Alistair Crooks added the code for the regex caching * agc - cached the regular expressions used - there's a good chance @@ -556,3 +556,12 @@ similar_escape(PG_FUNCTION_ARGS) PG_RETURN_TEXT_P(result); } + +/* + * report whether regex_flavor is currently BASIC + */ +bool +regex_flavor_is_basic(void) +{ + return (regex_flavor == REG_BASIC); +} -- cgit v1.2.3