On Sun, 5 Feb 2023 17:14:44 -0800 Peter Geoghegan <pg@xxxxxxx> wrote: ... > The OP should see the Postgres ICU docs for hints on how to use these > facilities to make a custom collation that matches whatever their > requirements are: > > https://www.postgresql.org/docs/current/collation.html#COLLATION-MANAGING As you are talking about ICU customization to match whatever the requirement we want, we were wondering if this would be that easy with ICU to build/create such custom and odd collation (and not just move numbers after latin)? Even being able to order letter by letter? For the record, I helped on an issue last week to sort data using the ebcdic order. ICU was just a pain, especially with this buggy and annoying bug when sorting numbers after letters[1] and the fact that it takes whatever we feed it with without complaining for badly formed or impossible collation. We just gave up. One of our recommendation was to write a glibc collation file, built/installed it using localedef and "import" it in PostgreSQL using pg_import_system_collations(). The customer actually did it and it works like a charm. Regards, [1] remember ? https://www.postgresql.org/message-id/flat/20200903105727.064665ce%40firost#0a6e89e58eec7679391c829231a7b3ea
