Re: GiST for range types (was Re: Range Types - typo + NULL string constructor)

On 03.11.2011 10:42, Jeff Davis wrote:
> On Wed, 2011-11-02 at 22:59 +0200, Heikki Linnakangas wrote:
>> This seems to be coming from the selectivity estimation function. The
>> selectivity function for<@ is scalargtsel, which is usually used for
>> scalar>  and>=. That doesn't seem right. But what do we store in the
>> statistics for range types in the first place, and what would be the
>> right thing to do for selectivity estimation?
>
> I'll have to think more about that, and it depends on the operator. It
> seems like an easier problem for "contains a point" than "contains
> another range" or "overlaps with another range".
>
> Right now I don't have a very good answer, and even for the "contains a
> point" case I'll have to think about the representation in pg_statistic.

I've committed this now, after some more cleanup. I removed the 
selectivity estimation functions from operators where they were bogus, 
so writing those is a clear TODO. But that can well be done as a 
separate patch.

Thanks!

-- 
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com