Stu Coates <[EMAIL PROTECTED]> writes: > I come from an Oracle background where I can lock an item of data by > performing a "SELECT FOR UPDATE" on the row. This is also implemented > in PostgreSQL. A quite useful feature Oracle does have is the ability > to add a "NOWAIT" clause to the end of the command which will cause an > exception if the item of data already has a lock taken out on it. > AFAIK, this is not implemented in PostgreSQL. I did see a note that > lock timeouts are not implemented, but if "NOWAIT" is added the > application developer could implement/fudge timeouts him/herself. Would > this be relatively easy to add? It'd be possible, but not particularly easy; anything that involves changing parse/plan trees is tedious. Moreover, I doubt that it'd be especially useful given the lack of nested transactions in Postgres. You'll have to make a lot better case than the above if you want to get anyone excited about the idea. regards, tom lane