Re: contsel and gist

Ben <midfield@gmail.com> writes:
> my guess is that it has to do with the selectivity of the @> operator.  i've looked and noticed that the selectivity
functionsfor @> and other period operators are basically stubs, with constant selectivity.  my questions are :
 

> 1 - am i wrong in my assessment?  is the constant contsel, areasel, etc hurting us?

The stub selectivity functions definitely suck.

> 2 - how hard would it be to implement contsel et al for period data types?

If it were easy, it'd likely have been done already :-(

However, having said that: the constant value of the stub contsel
function is intended to be small enough to encourage use of an
indexscan.  Maybe we just need to decrease it a bit more.  Have you
investigated what the cutover point is for your queries?
        regards, tom lane