Re: first post, need info on postgres + storing objects

On Thu, 14 Feb 2002, Joris Hilhorst wrote:

> if this is the wrong place to post, please let me know.
>
> I am trying to fix a mess on a system running a postgresql database (7.1 I
> think)
> java objects where stored on this server but it seems to me that when the
> rows
> holding the OID's of these objcets are deleted, or the tables holding the
> multiple
> rows is dropped, the attached objects aren't removed themselves.
>
> (I have double checked this assumptionof mine just now)
> for each OID with number yyyyyyyyyyy there is a file in the datadir named
> xinxyyyyyyyyyyy (header?) and a (value?) file of xinvyyyyyyyyyyy
>
> both files are not removed after dropping the rows linking to these files.
> am I doing something wrong here, or is this a 'feature'? Does anyone have
> similar problems?

Since AFAIK you can have multiple rows pointing to one object, and I could
see cases where someone would want to get the lo oid, delete a row and
insert a new one that points to that same lo rather than having to import
the lo again, it's hard to say. If you're not in one of those cases a
trigger on the table to do the cleanup is probably a good idea.

> I tried the vacuum function which only sizes down some system tables but
> leaves
> the object files untouched. Is there another function I should be looking
> into?

You might want to look at contrib/vacuumlo which looks for orphaned large
objects.