Re: [SQL] Performance - Mailing list pgsql-sql

Haven't created any yet, as I have not yet determined what I want to index
on.  I just created the database and bulk loaded 211 megs of : delimited
data, generating a 350 meg file in the data dir.  It has been vacuuming
for 45 mins or so now...  Prob needs more horsepower :D

Jason

---
Jason Slagle
Network Administrator - Toledo Internet Access - Toledo Ohio
- raistlin@tacorp.net - jslagle@toledolink.com - WHOIS JS10172

On Wed, 10 Mar 1999, Karl Denninger wrote:

> Depends on the indices that have to be gone through.  It can take quite a
> while.
>
> --
> --
> Karl Denninger (karl@denninger.net) http://www.mcs.net/~karl
> I ain't even *authorized* to speak for anyone other than myself, so give
> up now on trying to associate my words with any particular organization.
>
>
> On Wed, Mar 10, 1999 at 01:27:20PM -0500, Jason Slagle wrote:
> > And how long is normal for Vacuum analyze to take on bout 350 megs of
> > DATA?
> >
> > Jason
> >
> > ---
> > Jason Slagle
> > Network Administrator - Toledo Internet Access - Toledo Ohio
> > - raistlin@tacorp.net - jslagle@toledolink.com - WHOIS JS10172
> >
> > On Wed, 10 Mar 1999, Tom Lane wrote:
> >
> > > "Brett W. McCoy" <bmccoy@lan2wan.com> writes:
> > > >> I have 1,400,000 entries (200MB) I'm inserting into a database.  Radius
> > > >> detail files as a matter of fact.  Apart from COPY taking forever to load
> > > >> that (probably due to my several indexes), it seems the select is VERY
> > > >> slow.  Any tips?
> > >
> > > > I found that if you create an index before doing a bulk COPY, yes, it does
> > > > take forever to load, and the select is slow.  What I did was drop the
> > > > indices built from the COPY and rebuild them.  Speeded the selects up
> > > > significantly.  So now I don't build any indices until after I load my
> > > > huge databases in.
> > >
> > > Not building the indexes until you've done the bulk load is good advice;
> > > it does seem a lot faster to build an index on an already-loaded table
> > > than to construct it piecemeal during the COPY.  However, either way
> > > should result in the same index, so I don't see why it'd affect the
> > > speed of a subsequent SELECT.  Did you remember to do VACUUM ANALYZE
> > > both times?  The system is likely to ignore the index until you have
> > > vacuumed the table.
> > >
> > > In short, best bulk load procedure is
> > >
> > >     CREATE TABLE ...
> > >     COPY ...
> > >     CREATE INDEX(es) on table
> > >     Repeat as needed for all tables being bulk-loaded
> > >     VACUUM ANALYZE
> > >
> > > BTW, if you use pg_dump to dump and reload a big database, pg_dump
> > > knows about the create-indexes-last trick.  But it doesn't do a VACUUM
> > > for you; you have to do that by hand after running the reload script,
> > > or your database will be slow.
> > >
> > >             regards, tom lane
> > >
> >
> >
>