Re: Optimization for lower(), upper(), casefold() functions.

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>

To: Jeff Davis <pgsql@j-davis.com>

Cc: Alexander Borisov <lex.borisov@gmail.com>, Heikki Linnakangas <hlinnaka@iki.fi>, pgsql-hackers@postgresql.org

Date: 2025-03-18T15:11:41Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Fix headerscheck warning.
- 549ea06e4217 18.0 landed
Optimization for lower(), upper(), casefold() functions.
- 27bdec06841d 18.0 landed
Refactor convert_case() to prepare for optimizations.
- d3b2e5e1ab5c 18.0 landed
Improve performance of Unicode {de,re}composition in the backend
- 783f0cc64dcc 14.0 cited

One more thing: I observe that headerscheck is now unhappy:

$ src/tools/pginclude/headerscheck 
In file included from /tmp/headerscheck.yOpahZ/test.c:2:
./src/include/common/unicode_case_table.h:8598:24: warning: 'casekind_map' defined but not used [-Wunused-variable]
 static const pg_wchar *casekind_map[NCaseKind] =
                        ^~~~~~~~~~~~

It's not apparent to me why that table needs to be in a header
file and not in the sole user .c file?

Also, probably better to make it const:

-static const pg_wchar *casekind_map[NCaseKind] =
+static const pg_wchar * const casekind_map[NCaseKind] =

			regards, tom lane