Robert Haas wrote:
> Well, even if the table is not partitioned at all, I don't see that it
> should preclude parallel query access. If I've got a 1 GB table that
> needs to be sequentially scanned for rows meeting some restriction
> clause, and I have two CPUs and plenty of I/O bandwidth, ISTM it
> should be possible to have them each scan half of the table and
> combine the results. Now, this is not easy and there are probably
> substantial planner and executor changes required to make it work, but
> I don't know that it would be particularly easier if I had two 500 MB
> partitions instead of a single 1 GB table.
The point of partitioning in this scenario is primarily that you can put
the different partitions in different tablespaces, most likely on
independent disk devices. You therefore get more I/O bandwidth.
--
Craig Ringer