Re: Speed of locating tables? - Mailing list pgsql-general

From Tom Lane
Subject Re: Speed of locating tables?
Date
Msg-id 3708.959377527@sss.pgh.pa.us
Whole thread Raw
In response to Re: Speed of locating tables?  (Barry Lind <barry@xythos.com>)
List pgsql-general
Barry Lind <barry@xythos.com> writes:
> This sounds doable.  It would probably also remove the problem I have
> that unlinks of large objects can't be rolled back.

Right, lo_unlink would become something like
    "DELETE FROM pg_largeobjects WHERE loid = NNNN"
which is perfectly rollbackable.  This would also solve the problem a
number of people have had with accessing thousands of LOs in a single
transaction.  (The lock manager tends to run out of shared memory when
asked to keep track of that many table locks :-(.)

This might also make dump/restore of large objects more manageable,
since you'd just be talking about dumping & restoring the contents of
this one table instead of having to look around to see what LOs exist.

A disadvantage I didn't think of before is that it'd take extra work to
implement access protection of LOs --- we do not have any existing way
of protecting individual rows in a table...

            regards, tom lane

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