Re: BUG #19355: Attempt to insert data unexpectedly during concurrent update

On Mon, 2025-12-15 at 01:40 +0000, PG Bug reporting form wrote:
> Start two transaction and update on same tuple, raise concurrent update and
> evalplanqual.  It will be found out that the session with evalplanqual did
> not successfully update the data, but instead attempted to insert a row of
> data incorrectly.

I'd say that is expected.

If you need a guarantee that either INSERT or UPDATE succeed, you have to use
INSERT ... ON CONFLICT ... DO UPDATE

Yours,
Laurenz Albe