Robert Haas <robertmhaas@gmail.com> writes:
> What's hard about that? INSERTs are the hard case, because the rows
> you care about don't exist yet. SELECT, UPDATE, and DELETE are easy
> by comparison; you can lock the actual rows at issue. Unless I'm
> confused?
UPDATE isn't really any easier than INSERT: the update might cause
the row to satisfy someone else's search condition that it didn't
previously satisfy.
regards, tom lane
