Re: Primary key gist index?

On 03/14/2018 06:19 AM, Jeremy Finzel wrote:
> Hello!  From all that I can tell, it is not possible using a btree_gist
> index as a primary key.  If so, why not?  I have a table with this gist

https://www.postgresql.org/docs/10/static/btree-gist.html

"In general, these operator classes will not outperform the equivalent
standard B-tree index methods, and they lack one major feature of the
standard B-tree code: the ability to enforce uniqueness."

> index which truly ought to be its primary key.  as_of_date is of range
> date type:
>
> EXCLUDE USING gist (id WITH =, as_of_date WITH &&)
>
> Any direction here would be much appreciated.
>
> Right now, I am forced to create a redundant btree index UNIQUE, btree
> (id, lower(as_of_date)) in order to have a primary key on the table.
>
> Thanks!
> Jeremy

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com