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I have multiple tables in different geography types. For example, some are Point, some are PointZM, some are MultiPoint, etc. I need to convert all of them to PointZ. I have searched the documentation but find nothing. Does anyone know how to convert them? (Suggest the table I'd like to convert is "border", with a geography column named "geog".)

marked as duplicate by Andre Silva, BBG_GIS, BERA, nmtoken, HDunn Jan 2 at 7:14

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Converting geometric types of geography columns needs a cast to geometry support functions that don't support geography type (i.e. ST_Force3D in this question):

ALTER TABLE border ALTER COLUMN geog type geography(MultiPolygonZ, 4610) using ST_Force3D(geog::geometry)

The geog::geometry is the point.

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