I have a geometry column with mixed geometries like polygon, multi polygon. I am trying to set SRID for it using below query but I get the below error. What type of geometry has to be given when we have multi polygon and polygon type in one column?


ALTER TABLE geo_table
ALTER COLUMN geom TYPE geometry(POLYGON,4326) USING ST_TRANSFORM(ST_SetSRID(geometry,3857),4326)


ERROR:  Geometry type (MultiPolygon) does not match column type (Polygon)
  • 2
    I would force them to be all be multi using st_multi. then run your SRID command with multipolygon
    – ziggy
    Nov 9, 2022 at 17:39
  • 3
    Does this answer your question? Postgis change geometry type to Polygon
    – ziggy
    Nov 9, 2022 at 17:41
  • 1
    A generic geometry type "geometry" accepts all kind of geometries.
    – user30184
    Nov 9, 2022 at 17:58

1 Answer 1


you can use the generic geometry type. Also make sure to spell the proper column name in the using

ALTER TABLE geo_table
  ALTER COLUMN geom TYPE geometry(geometry,4326) 
    USING ST_TRANSFORM(ST_SetSRID(geom ,3857),4326);

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