postgresql/contrib/btree_gist
Tom Lane 9221f9d485 Make contrib/btree_gist's GiST penalty function a bit saner.
The previous coding supposed that the first differing bytes in two varlena
datums must have the same sign difference as their overall comparison
result.  This is obviously bogus for text strings in non-C locales, and
probably wrong for numeric, and even for bytea I think it was wrong on
machines where char is signed.  When the assumption failed, the function
could deliver a zero or negative penalty in situations where such a result
is quite ridiculous, leading the core GiST code to make very bad page-split
decisions.

To fix, take the absolute values of the byte-level differences.  Also,
switch the code to using unsigned char not just char, so that the behavior
will be consistent whether char is signed or not.

Per investigation of a trouble report from Tomas Vondra.  Back-patch to all
supported branches.
2013-02-07 19:13:59 -05:00
..
data Add missing newlines at end of files 2010-10-26 20:11:43 +03:00
expected Reduce messages about implicit indexes and sequences to DEBUG1. 2012-07-04 20:35:29 -04:00
sql Add KNNGIST support to contrib/btree_gist. 2011-03-02 14:44:33 -05:00
.gitignore Support "make check" in contrib 2011-04-25 22:27:11 +03:00
btree_bit.c Add postgres.h to *.c files for pg_upgrade, ltree, and btree_gist, and 2011-08-26 21:16:24 -04:00
btree_bytea.c Add postgres.h to *.c files for pg_upgrade, ltree, and btree_gist, and 2011-08-26 21:16:24 -04:00
btree_cash.c Remove many -Wcast-qual warnings 2011-09-11 21:54:32 +03:00
btree_date.c Remove many -Wcast-qual warnings 2011-09-11 21:54:32 +03:00
btree_float4.c Remove many -Wcast-qual warnings 2011-09-11 21:54:32 +03:00
btree_float8.c Remove many -Wcast-qual warnings 2011-09-11 21:54:32 +03:00
btree_gist--1.0.sql Throw a useful error message if an extension script file is fed to psql. 2011-10-12 15:45:03 -04:00
btree_gist--unpackaged--1.0.sql Throw a useful error message if an extension script file is fed to psql. 2011-10-12 15:45:03 -04:00
btree_gist.c Add postgres.h to *.c files for pg_upgrade, ltree, and btree_gist, and 2011-08-26 21:16:24 -04:00
btree_gist.control Convert contrib modules to use the extension facility. 2011-02-13 22:54:49 -05:00
btree_gist.h Remove unnecessary #include references, per pgrminclude script. 2011-09-01 10:04:27 -04:00
btree_inet.c Remove many -Wcast-qual warnings 2011-09-11 21:54:32 +03:00
btree_int2.c Replace int2/int4 in C code with int16/int32 2012-06-25 01:51:46 +03:00
btree_int4.c Replace int2/int4 in C code with int16/int32 2012-06-25 01:51:46 +03:00
btree_int8.c Remove many -Wcast-qual warnings 2011-09-11 21:54:32 +03:00
btree_interval.c Remove many -Wcast-qual warnings 2011-09-11 21:54:32 +03:00
btree_macaddr.c Remove many -Wcast-qual warnings 2011-09-11 21:54:32 +03:00
btree_numeric.c Add postgres.h to *.c files for pg_upgrade, ltree, and btree_gist, and 2011-08-26 21:16:24 -04:00
btree_oid.c Remove many -Wcast-qual warnings 2011-09-11 21:54:32 +03:00
btree_text.c Add postgres.h to *.c files for pg_upgrade, ltree, and btree_gist, and 2011-08-26 21:16:24 -04:00
btree_time.c Remove many -Wcast-qual warnings 2011-09-11 21:54:32 +03:00
btree_ts.c Remove many -Wcast-qual warnings 2011-09-11 21:54:32 +03:00
btree_utils_num.c Move Timestamp/Interval typedefs and basic macros into datatype/timestamp.h. 2011-09-09 13:23:41 -04:00
btree_utils_num.h Remove unnecessary #include references, per pgrminclude script. 2011-09-01 10:04:27 -04:00
btree_utils_var.c Make contrib/btree_gist's GiST penalty function a bit saner. 2013-02-07 19:13:59 -05:00
btree_utils_var.h Remove unnecessary #include references, per pgrminclude script. 2011-09-01 10:04:27 -04:00
Makefile Add -lm to SHLIB_LINK for contrib/btree_gist. 2011-03-03 01:43:38 -05:00