Rafael Martinez <r.m.guerrero@usit.uio.no> writes:
> Heikki Linnakangas wrote:
>> On a small table like that you could run VACUUM every few minutes
>> without much impact on performance. That should keep the table size in
>> check.
> Ok, we run VACUUM ANALYZE only one time a day, every night.
There's your problem.
Reading between the lines I gather that you think an update is "free"
in the sense of not creating a need for vacuum. It's not --- it's
exactly equivalent to an insert + a delete, and it leaves behind a
dead row that needs to be vacuumed. If you do a lot of updates, you
need to vacuum.
regards, tom lane
