postgresql/src
Tom Lane 05f4a88184 Fix bugs in gin_fuzzy_search_limit processing.
entryGetItem()'s three code paths each contained bugs associated
with filtering the entries for gin_fuzzy_search_limit.

The posting-tree path failed to advance "advancePast" after having
decided to filter an item.  If we ran out of items on the current
page and needed to advance to the next, what would actually happen
is that entryLoadMoreItems() would re-load the same page.  Eventually,
the random dropItem() test would accept one of the same items it'd
previously rejected, and we'd move on --- but it could take awhile
with small gin_fuzzy_search_limit.  To add insult to injury, this
case would inevitably cause entryLoadMoreItems() to decide it needed
to re-descend from the root, making things even slower.

The posting-list path failed to implement gin_fuzzy_search_limit
filtering at all, so that all entries in the posting list would
be returned.

The bitmap-result path used a "gotitem" variable that it failed to
update in the one place where it'd actually make a difference, ie
at the one "continue" statement.  I think this was unreachable in
practice, because if we'd looped around then it shouldn't be the
case that the entries on the new page are before advancePast.
Still, the "gotitem" variable was contributing nothing to either
clarity or correctness, so get rid of it.

Refactor all three loops so that the termination conditions are
more alike and less unreadable.

The code coverage report showed that we had no coverage at all for
the re-descend-from-root code path in entryLoadMoreItems(), which
seems like a very bad thing, so add a test case that exercises it.
We also had exactly no coverage for gin_fuzzy_search_limit, so add a
simplistic test case that at least hits those code paths a little bit.

Back-patch to all supported branches.

Adé Heyward and Tom Lane

Discussion: https://postgr.es/m/CAEknJCdS-dE1Heddptm7ay2xTbSeADbkaQ8bU2AXRCVC2LdtKQ@mail.gmail.com
2020-04-03 13:15:30 -04:00
..
backend Fix bugs in gin_fuzzy_search_limit processing. 2020-04-03 13:15:30 -04:00
bin Fix crash in psql when attempting to reuse old connection 2020-04-01 14:45:57 +09:00
common Fix command-line colorization on Windows with VT100-compatible environments 2020-03-02 15:46:24 +09:00
fe_utils Fix parallel restore of FKs to partitioned tables 2019-10-17 09:58:01 +02:00
include Re-implement the ereport() macro using __VA_ARGS__. 2020-03-24 11:48:33 -04:00
interfaces Allow ecpg to be built stand-alone, allow parallel libpq make 2020-03-31 14:17:32 -04:00
makefiles Select CFLAGS_SL at configure time, not in platform-specific Makefiles. 2019-10-21 12:32:35 -04:00
pl Ensure that plpgsql cleans up cleanly during parallel-worker exit. 2020-03-26 18:06:55 -04:00
port Be more careful about extracting encoding from locale strings on Windows. 2020-03-30 11:14:58 -04:00
template Select CFLAGS_SL at configure time, not in platform-specific Makefiles. 2019-10-21 12:32:35 -04:00
test Fix bugs in gin_fuzzy_search_limit processing. 2020-04-03 13:15:30 -04:00
timezone Update time zone data files to tzdata release 2019c. 2019-09-20 19:53:52 -04:00
tools Turn off deprecated bison warnings under MSVC 2020-03-20 14:02:05 -04:00
tutorial Phase 2 pgindent run for v12. 2019-05-22 13:04:48 -04:00
.gitignore Convert cvsignore to gitignore, and add .gitignore for build targets. 2010-09-22 12:57:04 +02:00
DEVELOPERS Replace a couple of references to files that no longer exist in the source 2009-05-04 08:08:47 +00:00
Makefile Fix partial-build problems introduced by having more generated headers. 2018-04-09 16:42:10 -04:00
Makefile.global.in Select CFLAGS_SL at configure time, not in platform-specific Makefiles. 2019-10-21 12:32:35 -04:00
Makefile.shlib Ensure static libraries have correct mod time even if ranlib messes it up. 2018-11-29 15:53:44 -05:00
nls-global.mk NLS: Fix backend gettext triggers 2019-09-23 09:05:50 +02:00