From: Tom Lane <tgl@sss.pgh.pa.us>
To: Glen Edmonds <glen.edmonds@gmail.com>
cc: "David G. Johnston" <david.g.johnston@gmail.com>,
        PostgreSQL mailing lists <pgsql-bugs@lists.postgresql.org>
Subject: Re: BUG #17428: last_value incorrect for uninitialized sequence
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Comments: In-reply-to Glen Edmonds <glen.edmonds@gmail.com>
	message dated "Tue, 08 Mar 2022 02:14:44 +1100"
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Glen Edmonds <glen.edmonds@gmail.com> writes:
> The problem really is that the two states of not initialized and post first
> usage are indistinguishable (both return 1), but the sequence next value is
> different.

They're not indistinguishable: if you look at the is_called flag
you'll see that it changes.

> ie it’s a reasonable expectation that the next value is
> last_value + 1. IMHO violating this makes it a bug.

You can call it that if you like, but it's operating as designed
and documented.  I fear it's about twenty years too late to propose
a redesign.

			regards, tom lane