Thread: How can i delete large objects from DB?

   Hi!
Man page on large objects describes how to create one, from file wit
lo_import, etc. But if i want delete row from the table which references
large object should I delete large object also? How can it be done ?
    Thanx in advance,
Sergei

> Man page on large objects describes how to create one, from file wit
> lo_import, etc. But if i want delete row from the table which references
> large object should I delete large object also? How can it be done ?

    Well, BLOBs aren't actually stored *in* tables, but you could do a
trigger mechanism that says ``if someone deletes something from this table, do
this'' ...this being, ``lo_unlink(that blob)''

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On Mon, 3 Aug 1998, Dustin Sallings wrote:

> > Man page on large objects describes how to create one, from file wit
> > lo_import, etc. But if i want delete row from the table which references
> > large object should I delete large object also? How can it be done ?
>
>     Well, BLOBs aren't actually stored *in* tables, but you could do a
> trigger mechanism that says ``if someone deletes something from this table, do
> this'' ...this being, ``lo_unlink(that blob)''

An example of such a trigger is in the current development source (in
contrib/lo).

I'm currently working on a fix for orphaning (which is when a row
containing a reference to a blob is deleted, but the blob remains). I have
a possible solution, but currently cannot test it as postgresql is
currently broken on my machine.

--
Peter T Mount peter@retep.org.uk or petermount@earthling.net
Main Homepage: http://www.retep.org.uk
PostgreSQL JDBC Faq: http://www.retep.org.uk/postgres