Re: COPY from question

Kevin Brown <kevin(at)sysexperts(dot)com> writes:
> Slavisa Garic wrote:
>> Using pg module in python I am trying to run the COPY command to populate
>> the large table. I am using this to replace the INSERT which takes about
>> few hours to add 70000 entries where copy takes minute and a half.

> That difference in speed seems quite large. Too large. Are you batching
> your INSERTs into transactions (you should be in order to get good
> performance)? Do you have a ton of indexes on the table? Does it have
> triggers on it or some other thing (if so then COPY may well wind up doing
> the wrong thing since the triggers won't fire for the rows it
> inserts)?

COPY *does* fire triggers, and has done so for quite a few releases.

My bet is that the issue is failing to batch individual INSERTs into
transactions. On a properly-set-up machine you can't get more than one
transaction commit per client per disk revolution, so the penalty for
trivial transactions like single inserts is pretty steep.

regards, tom lane