[gdal-dev] What do people think of the MySQL Spatial Extensions?

[pcreso at pcreso.com]

Russell McOrmond wrote:
> I am aware of PostGIS, Oracle Spatial and ArcSDE.  I only became aware
> that MySQL had extensions as well very recently (My
> brother started at Pythian).
> 
>  http://dev.mysql.com/doc/refman/5.5/en/mysql-gis-conformance-and-compatibility.html
> http://www.gdal.org/ogr/drv_mysql.html
> 
> Are there people in this list that use this extensively, and can give
> some comparisons to other databases/etc?
> 
> Thanks!

The databases I'm aware of with OGC SFS support include Oracle, PostGIS, SLQ SErver 2008, Informix, DB2, Ingres & SpatialLite. In the large datawarehouse environment, Teradata & Netezza also have offerings with similar functionality.

As far as MySQL goes, I'd consider their implementation fundamentally broken.

If you look here, it suggests there is full robust support.
http://dev.mysql.com/doc/refman/5.5/en/spatial-extensions.html
http://dev.mysql.com/doc/refman/5.5/en/mysql-gis-conformance-and-compatibility.html


then see this page:
http://dev.mysql.com/doc/refman/5.5/en/functions-that-test-spatial-relationships-between-geometries.html

So, for example, if you ask MySQL to return the points lying in a circle. triangle or any non-linear, non-rectangular polygon, it will happily return all the points that lie within the rectangular bounding box of this polygon, which is NOT what it was asked to do.

I don't like databases that return wrong answers, or that release something like this as production ready & leave it in this state for several years. But if you just want to store the data & never use spatial relationship queies on itm, then I guess it will work.

HTH,

  Brent Wood