In article <25074.1012924704@sss.pgh.pa.us> in newsgroup
comp.databases.postgresql.general on Tue, 5 Feb 2002 16:10:06 +0000
(UTC), Tom Lane(tgl@sss.pgh.pa.us) said...
> Patrick Dunford <dunfordsoft@clear.net.nz> writes:
> > Using pgsql 7.1.3 I have found that on occasions, there is no reply to an
> > SQL statement like
>
> > ALTER TABLE x
> > ADD COLUMN y z
>
> You sure it's not just waiting for some other transaction to give up a
> lock on the table? ALTER TABLE ADD COLUMN should be essentially
> instantaneous, since it doesn't touch the table data. But it needs to
> get exclusive lock on the table first.
Well if it doesn't send a message back to the client then there is no way
of knowing this.
I had it do the same thing on two Drop Table requests, eventually it came
back and said the relation does not exist so I knew then it had dropped
the table but not because it had replied to the first request.