Thread: pgsql: Handle empty-string edge cases correctly in strpos().
Handle empty-string edge cases correctly in strpos(). Commit 9556aa01c rearranged the innards of text_position() in a way that would make it not work for empty search strings. Which is fine, because all callers of that code special-case an empty pattern in some way. However, the primary use-case (text_position itself) got special-cased incorrectly: historically it's returned 1 not 0 for an empty search string. Restore the historical behavior. Per complaint from Austin Drenski (via Shay Rojansky). Back-patch to v12 where it got broken. Discussion: https://postgr.es/m/CADT4RqAz7oN4vkPir86Kg1_mQBmBxCp-L_=9vRpgSNPJf0KRkw@mail.gmail.com Branch ------ REL_12_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/43e43771bc4b03a9e33be7261cc84dc7f65ae9ef Modified Files -------------- src/backend/utils/adt/varlena.c | 10 +++++++++- src/test/regress/expected/strings.out | 18 ++++++++++++++++++ src/test/regress/sql/strings.sql | 6 ++++++ 3 files changed, 33 insertions(+), 1 deletion(-)