[postgis-users] how to determine a geometry type?

nguyen liem liemnguyendl at gmail.com
Sat Jul 3 00:30:50 PDT 2010

Hi Luís

I have a table "mytable" with 2 columns: "id" and "mygeo".
"mygeo" with geometry type is POINT

I used "GeometryType" function to determine what geometry type of column
   - SELECT GeometryType(mygeo) FROM mytable;
If "mytable" table has no data that the result of above query is NULL (*I
can't know geometry type of column "mygeo"* )
If "mytable" table has data that the result is "POINT"

how to know a geometry type of "mytable" column if it has no data? Using
"GeometryType" function or anothers functions to chek it.


2010/7/2 Luís de Sousa <luis.a.de.sousa at gmail.com>

> Hi nguyen,
> Though the select Nicolas sent will inform you of the type recorded in
> the PostGis tables, this may not be coincident with the type of your
> table's geometry. The exact type is the one checked by the
> enforce_geotype constraint.
> Luís
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Liem Nguyen
Axon Active Corp.
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