Re: Server error and deadlocks

You're right about the lack of foreign keys... it's a foreign concept to the
DUHvelopers. I suspect table locks but are there any database level tracing
tools to show the SQL? Will the trace_locks and debug_deadlocks parameters
help and how do I use them?

TIA

-----Original Message-----
From: Tom Lane [mailto:tgl(at)sss(dot)pgh(dot)pa(dot)us]
Sent: Monday, January 13, 2003 9:18 PM
To: Stephan Szabo
Cc: Orr, Steve; pgsql-general(at)postgresql(dot)org
Subject: Re: [GENERAL] Server error and deadlocks

Stephan Szabo <sszabo(at)megazone23(dot)bigpanda(dot)com> writes:
> On Mon, 13 Jan 2003, Orr, Steve wrote:
>> Finally, there are LOTS of deadlocks and I'm thinking it's because they
are
>> not doing "SELECT ... FOR UPDATE" or are explictly locking tables. Or
they
>> are constantly updating the same rows. It seems our duhvelopers need to
get

> Well, if you're using foreign keys, you might be running into a deficiency
> in the foreign key implementation.

If these folk are immigrants from MySQL, I bet they're not using foreign
keys. Taking table-level locks seems like a more likely route to
deadlock. But this is all guesswork --- we need to see some info about
the queries being issued before we can opine about the real cause.

regards, tom lane