Re: Postgres scalability and performance on windows - Mailing list pgsql-performance

"Gopal" <gopal@getmapping.com> writes:
> This is the query and the schema....
> ...
>                         select
> sum(area(intersection(snaptogrid(chunkgeometry,0.00000001),
>                         GeometryFromText('POLYGON((-0.140030845589332
> 50.8208343077265,-0.138958398039148 50.8478005422809,-0.0963639712296823
> 50.8471133071392,-0.0974609286275892 50.8201477285483,-0.140030845589332
> 50.8208343077265))',4326))) * 100/ (0.00114901195862628)) as
> percentCover,

So evidently area(intersection(snaptogrid(...))) takes about 300
microsec per row.  The PostGIS hackers would have to comment on whether
that seems out-of-line or not, and whether you can make it faster.

            regards, tom lane