postgresql/src
Jeff Davis ea1db8ae70 Canonicalize ICU locale names to language tags.
Convert to BCP47 language tags before storing in the catalog, except
during binary upgrade or when the locale comes from an existing
collation or template database.

The resulting language tags can vary slightly between ICU
versions. For instance, "@colBackwards=yes" is converted to
"und-u-kb-true" in older versions of ICU, and to the simpler (but
equivalent) "und-u-kb" in newer versions.

The process of canonicalizing to a language tag also understands more
input locale string formats than ucol_open(). For instance,
"fr_CA.UTF-8" is misinterpreted by ucol_open() and the region is
ignored; effectively treating it the same as the locale "fr" and
opening the wrong collator. Canonicalization properly interprets the
language and region, resulting in the language tag "fr-CA", which can
then be understood by ucol_open().

This commit fixes a problem in prior versions due to ucol_open()
misinterpreting locale strings as described above. For instance,
creating an ICU collation with locale "fr_CA.UTF-8" would store that
string directly in the catalog, which would later be passed to (and
misinterpreted by) ucol_open(). After this commit, the locale string
will be canonicalized to language tag "fr-CA" in the catalog, which
will be properly understood by ucol_open(). Because this fix affects
the resulting collator, we cannot change the locale string stored in
the catalog for existing databases or collations; otherwise we'd risk
corrupting indexes. Therefore, only canonicalize locales for
newly-created (not upgraded) collations/databases. For similar
reasons, do not backport.

Discussion: https://postgr.es/m/8c7af6820aed94dc7bc259d2aa7f9663518e6137.camel@j-davis.com
Reviewed-by: Peter Eisentraut
2023-04-04 10:38:58 -07:00
..
backend Canonicalize ICU locale names to language tags. 2023-04-04 10:38:58 -07:00
bin Canonicalize ICU locale names to language tags. 2023-04-04 10:38:58 -07:00
common Make SCRAM iteration count configurable 2023-03-27 09:46:29 +02:00
fe_utils Revert refactoring of restore command code to shell_restore.c 2023-02-06 08:28:42 +09:00
include Canonicalize ICU locale names to language tags. 2023-04-04 10:38:58 -07:00
interfaces Code review for recent SQL/JSON commits 2023-04-04 14:04:30 +02:00
makefiles meson: Make auto the default of the ssl option 2023-03-13 07:04:11 +01:00
pl Add a way to get the current function's OID in pl/pgsql. 2023-04-04 13:33:18 -04:00
port Use nanosleep() to implement pg_usleep(). 2023-03-15 17:57:12 +13:00
template Use unnamed POSIX semaphores on Cygwin. 2023-01-06 10:33:28 +13:00
test Canonicalize ICU locale names to language tags. 2023-04-04 10:38:58 -07:00
timezone Fix outdated references to guc.c 2023-03-02 13:49:39 +01:00
tools Revert 11470f544e 2023-04-03 16:54:31 +03:00
tutorial Remove useless casts to (void *) in arguments of some system functions 2023-02-07 06:57:59 +01:00
.gitignore
DEVELOPERS
Makefile Integrate pg_bsd_indent into our build/test infrastructure. 2023-02-12 12:22:21 -05:00
Makefile.global.in pg_regress: Emit TAP compliant output 2023-03-31 13:00:02 +02:00
Makefile.shlib autoconf: Rely on ar supporting index creation 2022-10-07 11:53:39 -07:00
meson.build Integrate pg_bsd_indent into our build/test infrastructure. 2023-02-12 12:22:21 -05:00
nls-global.mk Fix for make unportability 2022-07-13 09:15:01 +02:00