Neil Conway <neilc@samurai.com> writes:
> On Tue, 2005-02-01 at 11:24 -0300, Alvaro Herrera wrote:
>> How about the TID?
> That wouldn't be sufficiently stable for use by client applications, I
> believe: a concurrent VACUUM FULL could mean your TID no longer points
> at what you think it does.
It'd be safe enough within the same transaction, since VACUUM can't kill
a tuple inserted by an open transaction; nor could VACUUM FULL touch the
table at all, since you'll be holding at least a writer's lock on the
table.
But this is all moot since INSERT/UPDATE RETURNING is really the way to
go, on grounds of functionality, speed, and not breaking backward
compatibility for existing client code.
regards, tom lane