Ed Loehr wrote:
>
> Question: is it safe to insert/update/delete during VACUUM?
>
It is supposed to be (MVCC should take care of it), but in practice I've
got bad experiences with it. The system should at least have a very low
load. You can get dead-lock errors, as the tables being vacuumed are
locked for a long time and then inaccessible to other queries (that's
unavoidable, but still annoying). And a couple of times something went
wrong and I ended up with duplicate tuples in my tables -- really
duplicate, including the oid's. That required a table
dump/sort/uniq/load to fix :-(.
Adriaan