s post <[EMAIL PROTECTED]> writes: > Recently I posted "notes on SERIALIZABLE transactions". In these notes I > state that one should use SELECT FOR UPDATE on all accessed data items to > execute SERIALIZABLE transactions. I now seem to have found a schedule > that cannot be serialized in this way.
Congratulations, you've discovered the need for predicate locking ;-) I'm not sure why this wasn't well-documented long ago, but I've added something to the 8.0 docs about it: http://developer.postgresql.org/docs/postgres/transaction-iso.html#MVCC-SERIALIZABILITY > If so, then I suppose this is a bug? We do not consider it a bug ... at least, doing predicate locking is not on our list of desirable changes. In practice, using explicit table locking when necessary is a much more effective solution to these types of problems. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly
