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In my table I have a column "location" that is a POINT. I tried this:

SELECT ST_X(location), ST_Y(location) FROM locations;

But I still get the error message: ERROR: function st_x(point) does not exist

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If you execute the query SELECT ST_X(ST_GeomFromEWKT('POINT(1 2 3 4)')); does it work or get any error? – juanluisrp Jun 26 '13 at 9:46
it returns "1". I have the postgis extension added – George Hown Jun 26 '13 at 12:09
what do you get from "\d locations" and "select * from locations"? paste here the first 5 lines of the latter query – Gery Jun 26 '13 at 12:17
up vote 1 down vote accepted

It looks like your column location type is point (PostgreSQL reference). This is a native PostgreSQL type, not an Postgis datatype.

You have to change location column data type to geometry or add a new geometry column with the Postgis function AddGeometryColumn.

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It works now! Thanks – George Hown Jun 26 '13 at 17:26

you need to use:

SELECT ST_X(geom), ST_Y(geom) FROM locations;

I suppose that locations is a table of points with the geometry named as "geom".

Hope this helps,

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Property Value Name location Position 35 Data type point Collation Default Sequence Not NULL? No Primary key? No Foreign key? No Storage PLAIN Inherited No Statistics -1 System column? No I don't understand what you mean with this comment – Gery Jun 26 '13 at 12:21
my "location" column field table properties...I dont know how to edit this nicely :( – George Hown Jun 26 '13 at 13:07

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