"David G. Johnston" <david.g.johnston@gmail.com> writes:
> If you actually perform that algorithm manually using two psql sessions you
> will find, if done properly, that the row with id=4 exists. If it does not
> then show that work because you will indeed have found a bug. But as of
> now you have not demonstrated a bug in PostgreSQL.
Yeah. This could be a Postgres problem, or it could be an application
problem. Given the lack of other similar reports, the a-priori
assumption has to be that it's an application problem. In any case,
there's no way for the rest of us to investigate since we don't have
access to either the application or data involved.
regards, tom lane