JD, On Wednesday, November 4, 2015, Joshua D. Drake <j...@commandprompt.com> wrote:
> On 11/04/2015 02:15 PM, Stephen Frost wrote: > > Yeah but anything holding a lock that long can be terminated via >>> statement_timeout can it not? >>> >> >> Well, no? statement_timeout is per-statement, while transaction_timeout >> is, well, per transaction. If there's a process which is going and has >> an open transaction and it's holding locks, that can be an issue. >> > > No, what I mean is this: > > BEGIN; > select * from foo; > update bar; > delete baz; > > Each one of those is subject to statement_timeout, yes? If so, then I > don't see a point for transaction timeout. You set statement_timeout for > what works for your environment. Once the timeout is reached within the > statement (within the transaction), the transaction is going to rollback > too. > This implies that a statement used takes a long time. It may not. The lock is held at the transaction level not the statement level, which is why a transaction level timeout is actually more useful than a statement level timeout. What I'm most interested in, in the use case which I described and which David built a system for, is getting that lock released from the lower priority process to let the higher priority process run. I couldn't care less about statement level anything. Thanks! Stephen
