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I'm using PostGIS to add geometry columns to tables, but keep receiving the error:

ERROR: function addgeometrycolumn(character varying, character varying, integer, character varying, integer) is not unique
SQL state: 42725
Hint: Could not choose a best candidate function. You might need to add explicit type casts.

The statement I am trying to call is:

SELECT addGeometryColumn('schema', 'table', 'geom', 3857, 'POINT', 2);

I have tried type-casting each argument but I received the same message. I have also removed and re-installed the postgis extension, which made no difference.

I have used this function countless times before and am somewhat puzzled as to why it isn't working all of a sudden. I have also tried a few other postgis functions which gave me similar errors.

I am considering reinstalling postgresql/postgis but I will have to spend time reconfiguring the set-up so I am hoping there is an easier way to fix/get around this.

Does anybody have any advice as to what may be causing this?

share|improve this question
duplicate:… – mkennedy Jun 14 '13 at 21:04

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