Tom Lane wrote: > Yeah, and it's exactly at the level of quirks that things are likely > to change. Nobody's going to suddenly start sorting B before A. > They might, say, change their minds about where the digram "cz" > sorts relative to single letters, in languages where special rules > for that are a thing.
Independently of these rules, all Unicode collations change frequently because each release of Unicode adds new characters. Any string that contains a code point that was previously unassigned is going to be sorted differently by all collations when that code point gets assigned to a character. Therefore the versions of all collations need to be bumped at every Unicode release. This is what ICU does. If the libc in macOS doesn't follow Unicode, that's not relevant to macOS, but let's assume an OS that tries to be up-to-date. If major OS upgrades happen every year or less frequently, each OS upgrade is likely to imply an upgrade of all the collations, since the interval between Unicode releases tends to be a year or less: https://www.unicode.org/history/publicationdates.html Best regards, -- Daniel Vérité https://postgresql.verite.pro/ Twitter: @DanielVerite
