Re: Support retrieving value from any sequence

On 7/14/15 12:06 PM, Tom Lane wrote:
> Thom Brown <thom@linux.com> writes:
>> On 14 July 2015 at 17:17, Robert Haas <robertmhaas@gmail.com> wrote:
>>> Since it's trivial to define this function if you need it, I'm not
>>> sure there's a reason to include it in core.
>
>> It's not always possible to create functions on a system when access
>> is restricted.  It may even be the case that procedural languages are
>> prohibited, and plpgsql has been removed.
>
> By that argument, *any* random function has to be in the core.
>
> I really don't see what's wrong with "SELECT last_value FROM sequence",
> especially since that has worked in every Postgres version since 6.x.
> Anyone slightly worried about backwards compatibility wouldn't use
> an equivalent function even if we did add one.

Because you can't do that for all functions in a database.

FWIW, I think it'd be better to have a pg_sequences view that's the 
equivalent of SELECT * FROM <sequence> for every sequence in the 
database. That would let you get whatever info you needed.
-- 
Jim Nasby, Data Architect, Blue Treble Consulting, Austin TX
Data in Trouble? Get it in Treble! http://BlueTreble.com