On Thu, Feb 09, 2006 at 04:14:09PM -0700, Jan Peterson wrote:
> In my experience, you don't want to store this stuff in the database. 
> In general, it will work fine, until you have to VACUUM the
> pg_largeobject table.  Unless you have a very powerful I/O subsystem,
> this VACUUM will kill your performance.

Good point about the vacuum issue; I haven't had to deal with vacuuming
very large objects.

> > You're forgetting about cleanup and transactions. If you store outside
> > the database you either have to write some kind of garbage collector, or
> > you add a trigger to delete the file on disk when the row in the
> > database pointing at it is deleted and hope that the transaction doesn't
> > rollback.
> 
> Our solution to this problem was to have a separate table of "external
> files to delete".  When you want to delete a file, you just stuff an
> entry into this table.  If your transaction rolls back, so does your
> insert into this table.  You have a separate thread that periodically
> walks this table and zaps the files from the filesystem.

Sure, there's lots of ways around it. My point was that there *is* a
tradeoff.
-- 
Jim C. Nasby, Sr. Engineering Consultant      [EMAIL PROTECTED]
Pervasive Software      http://pervasive.com    work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf       cell: 512-569-9461

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