Chris Campbell <chris@bignerdranch.com> writes:
> ERROR: deadlock detected
> DETAIL: Process 1120 waits for ShareLock on transaction 5847116;
> blocked by process 1171.
> Process 1171 waits for ExclusiveLock on tuple (6549,28) of relation
> 37637 of database 37574; blocked by process 1120.
> Relation 37636 is the users table (schema attached).
> Process 1120 was running an UPDATE query and changing a single row in
> the users table.
And what was 1171 doing? I really doubt that either of these could have
been pg_dump.
Given that you appear to be running 8.1 (tut-tut for not saying), it
really shouldn't be a foreign key problem either. I'm betting these
are just flat out conflicting updates of the same row(s).
regards, tom lane