Re: Chatter on DROP SOMETHING IF EXISTS

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Eisentraut <peter_e@gmx.net>
Cc: Alvaro Herrera <alvherre@commandprompt.com>, Bruce Momjian <bruce@momjian.us>, "Jim C. Nasby" <jim@nasby.net>, Andrew Dunstan <andrew@dunslane.net>, pgsql-hackers@postgresql.org
Date: 2007-02-19T14:57:32Z
Lists: pgsql-hackers
Peter Eisentraut <peter_e@gmx.net> writes:
> Am Montag, 19. Februar 2007 13:12 schrieb Alvaro Herrera:
>> I don't understand -- what problem you got with "NO OPERATION"?  It
>> seemed a sound idea to me.

> It seems nonorthogonal.  What if only some of the tables you mentioned did not 
> exist?  Do you get "SOME OPERATION"?

I'd say you get DROP TABLE as long as at least one table was dropped.

> There are also other cases where commands don't have an effect but we don't 
> explicitly point that out.

The precedent that I'm thinking about is that the command tag for COMMIT
varies depending on what it actually did.

regression=# begin;
BEGIN
regression=# select 1/0;
ERROR:  division by zero
regression=# commit;
ROLLBACK
regression=#

			regards, tom lane