Re: Re: unique sequences

I imagine it should if you create a unique index on the field.

Cheers,
Christopher Currie


----- Original Message -----
From: K Parker <kparker@eudoramail.com>
To: <pgsql-sql@hub.org>
Sent: Tuesday, June 27, 2000 1:52 AM
Subject: [SQL] Re: unique sequences


> > Rather, each time you wish to do an insert,
> > query the existing data to see what the
> > maximum value is existing in the database.
> > Add 1 to that and use this as your new value.
> > This is guaranteed to not have any holes in
> > the sequence.
>
> True, but alas it _doesn't_ guarantee uniqueness, since there's nothing to
prohibit 2 or more back ends getting the same max() at the
> same time...
>
> Thinking off the top of my head, I'm not sure you can apply FOR UPDATE to
an aggregate function, so there's probably no solution there, either.
>
>
>
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