Because people can be smarter about the data partitioning.
Consider a table of users. Some are active, most are not. The active
users account for nearly all of the users table access, but I still
(occasionally) want to access info about the inactive users.
Partitioning users into active_users and inactive_users allows me to
tell the database (indirectly) that the active users index should stay
in memory, while the inactive users can relegated to disk.
-Nathan
On Thu, May 1, 2008 at 6:02 AM, Jeremy Harris <jgh@wizmail.org> wrote:
> Gurjeet Singh wrote:
>
> > One of the advantages
> > of breaking up your data into partitions, as professed by Simon (I think)
> > (and I agree), is that you have smaller indexes, which improve
> performance.
> > And maybe having one huge index managing the uniqueness across partitioned
> > data just defeats the idea of data partitioning!
> >
>
> Isn't "large indexes are a performance problem" just saying
> "we don't implement indexes very well"? And why are they
> a problem - surely a tree-structured index is giving you
> range-partitioned subsets as you traverse it? Why is this
> different from manual partitioning into (inherited) tables?
>
> Thanks,
> Jeremy
>
>
>
> --
> Sent via pgsql-general mailing list (pgsql-general@postgresql.org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-general
>
