UPDATE .. RETURNING OLD.*

Hi everyone,

Today I needed a feature like $subject. The use case was: UPDATE foo SET
bar = bar + 1 WHERE id=$1, but I wanted to only do it when bar was 0. In
order to give the user an informative error message, I also needed to
distinguish the two cases: a row with id = $1 doesn't exist, and bar was
0, so I couldn't put bar != 0 into the WHERE clause. This time I got
around it by using RETURNING bar and checking that it was 1 on the
client side, but I can come up with other cases where you can't do that.

Comments?

Regards,
Marko Tiikkaja