Re: Sequence Access Method WIP

On 20/04/15 12:05, Andres Freund wrote:
> On 2015-04-20 12:49:39 +0300, Heikki Linnakangas wrote:
>> With the patch, pg_class.relam column references to the pg_seqam table for
>> sequences, but pg_indexam for indexes. I believe it's the first instance
>> where we reuse a "foreign key" column like that. It's not a real foreign
>> key, of course - that wouldn't work with a real foreign key at all - but
>> it's a bit strange. That makes me a bit uncomfortable. How do others feel
>> about that?
>
> Hm. I'd modeled it more as an extension of the 'relkind' column
> mentally. I.e. it further specifies how exactly the relation is
> behaving. Given that the field has been added to pg_class and not
> pg_index, combined with it not having index in its name, makes me think
> that it actually was intended to be used the way it's done in the patch.
>

That's how I think about it too. It's also short for access method, 
nothing really suggests to me that it should be index specific by design.


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