Re: alter enum add value if not exists

Andrew Dunstan <andrew@dunslane.net>

From: Andrew Dunstan <andrew@dunslane.net>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Magnus Hagander <magnus@hagander.net>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2012-09-22T17:06:08Z
Lists: pgsql-hackers
On 09/20/2012 06:34 PM, Tom Lane wrote:
> Andrew Dunstan <andrew@dunslane.net> writes:
>> On 08/23/2012 07:39 AM, Magnus Hagander wrote:
>>> It doesn't break, of course ,since it's protected by the unique index.
>>> But aren't you at risk of getting the very error message you're trying
>>> to avoid?
>> Yeah, looking further this was probably a thinko on my part. Thanks for
>> noticing. I've moved the test down so it's done right after the lock is
>> acquired. Revised patch attached.
> This patch looks sane as far as it goes.  It strikes me though that if
> we're going to invent an opt_if_not_exists production in the grammar,
> there are a lot of other places where it should be used too, for
> consistency if nothing else.
>
> However, it would be reasonable to do that mop-up as a separate
> commit.  If you prefer, commit what you've got and then I'll see
> about the other thing.
>
> 			


The enum piece is now committed.

I agree cleaning this up would be a good idea.

cheers

andrew