Bruce Momjian <[email protected]> writes:
> On Sat, Oct 31, 2026 at 11:24:33PM -0400, shihao zhong wrote:
>> The attached patch adds a short entry that tells people to REINDEX them
>> after upgrading. It is for REL_19_STABLE only. Would you add it?
> The general issue is that PG 19 is assumed to include all changes in all
> the minor releases so far. Therefore, I don't think this belongs in the
> PG 19 major release notes.
Also, the proposed text is too alarmist, because it claims that
indexes on CHAR(n) columns need to be reindexed. AFAICS that is not
true: CHAR(n) forces the number of characters to match in all entries
in the column, therefore two otherwise-equal strings will have the
same number of trailing blanks and will compare bitwise equal anyway.
So you are only at risk if you created an unconstrained "bpchar"
column, which is surely a pretty tiny minority usage.
I did list this first in the draft 18.7 release notes, but mostly
by default: there are not too many entries that require DBA action.
I think the number of people actually affected will be small,
likely smaller than the number of people who need to worry about
reindexing other kinds of indexes.
(To that point, if we did mention reindexing issues in major release
notes, we'd have to cover those other bugs too.)
regards, tom lane
