Re: [BUGS] Status of issue 4593

>>> Josh Berkus <josh@agliodbs.com> wrote: 
> That's not how SELECT FOR UPDATE works.  SFU is pessimistic manual 
> locking, which is supposed to *wait* for the rows to be exclusively 
> available.  The deadlock timeout you encountered is the correct 
> behaviour, not "serialization failure", which is what happens at
commit 
> time when the engine realizes that concurrent transactions are not 
> serializably recreateable.
Deadlocks like this are the only kind of serialization error possible
under "traditional" (non-MVCC) databases.  These are much more rare in
MVCC than update conflicts, but that doesn't mean they aren't
serialization failures there, too.  I think it is a violation of the
standard for PostgreSQL not to report them with SQLSTATE '40001'.
-Kevin