Re: Simple query, 10 million records...MySQL ten times faster

On 4/27/07, Alexander Staubo <alex@purefiction.net> wrote:
[snip]
> PostGIS implements the whole GIS stack, and it's so good at this that
> it's practically the de facto tool among GIS analysts. Installing
> PostGIS into a database is simple, and once you have done this, you
> can augment your table with a geometry (*):
>
>   alter table test_zip_assoc add column lonlat geometry;

I forgot to include the crucial step, of course:

  create index test_zip_assoc_lonlat_index on test_zip_assoc
    using gist (lonlat gist_geometry_ops);
  analyze test_zip_assoc_lonlat;

This creates a GiST index on the geometry and (significantly) updates
the table statistics.

Alexander.