I wrote:
> PG Bug reporting form <noreply@postgresql.org> writes:
>> [ updating via a view fails to recalculate GENERATED columns ]
> Yeah, that's surely a bug. In fact, it's a regression, because
> the test case works as-expected in v12. Not sure where we broke it.
git bisect blames
c6679e4fca21d253ced84c51ac1a31c1b2aec72f is the first bad commit
commit c6679e4fca21d253ced84c51ac1a31c1b2aec72f
Author: Peter Eisentraut <peter@eisentraut.org>
Date: Mon Feb 17 15:19:58 2020 +0100
Optimize update of tables with generated columns
When updating a table row with generated columns, only recompute those
generated columns whose base columns have changed in this update and
keep the rest unchanged. This can result in a significant performance
benefit. The required information was already kept in
RangeTblEntry.extraUpdatedCols; we just have to make use of it.
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/b05e781a-fa16-6b52-6738-761181204567@2ndquadrant.com
regards, tom lane