> On Jan 21, 2019, at 3:27 PM, Andres Freund <andres@anarazel.de> wrote:
>
> Hi,
>
> On 2019-01-21 15:21:29 -0800, Paul Ramsey wrote:
>> As a practical matter, most of the exact-test functions have a
>> preamble that checks the bbox, so in the seqscan case having the
>> operator along for the ride isn’t any advantage. In any event, if we
>> do have exact tests w/o a lossy preamble, we could add that for v12,
>> as this renovation won’t be a small one if we go this direction.
>
> How expensive are the bbox checks in comparison to the exact tests? IOW,
> how much of a problem is it to potentially do a bbox check twice?
Very very cheap. The geometry object usually has a bbox already instantiated and stored along with the actual
coordinates.The exceptions are objects (points, two-vertex lines) that are basically their own boxes anyways.
P
>
> Greetings,
>
> Andres Freund