Re: [HACKERS] psql - add special variable to reflect the last query status

I think you're overly optimistic to believe that every failure will
have a SQLSTATE; I don't think that's true for libpq-reported errors,
such as connection loss.

Yep, I thought I was optimistic:-) Can I add a special SQLSTATE for that
situation where libpq did not report an error?

Meh.  If we're going to do that I think it might be better to hack
libpq itself to do so, ie, force PQresultErrorField(..., PG_DIAG_SQLSTATE)
to always return something.  But it seems like a hack either way.

I would not have took the liberty to hack into libpq internals for such a small front-end feature. However I agree that having libpq always return some diagnostic, even if it means "something unclear happened, sorry not to be very precise", would be better.

--
Fabien.