Thread: How fair is SELECT FOR UPDATE ?

Hi all,

I wonder how fair is the lock allocation of SELECT FOR UPDATE ?
Is it fair, i.e. the first transaction which requested the lock will get
it, or it is possible that new requests are served quicker ?

TIA,
Csaba.

Csaba Nagy <nagy@ecircle-ag.com> writes:
> I wonder how fair is the lock allocation of SELECT FOR UPDATE ?
> Is it fair, i.e. the first transaction which requested the lock will get
> it, or it is possible that new requests are served quicker ?

8.1 will guarantee first-come-first-served for row-level locks, but
prior releases make no guarantees.

            regards, tom lane