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I added a new column by:

SELECT AddGeometryColumn('table_name', 'column_name', 4326, 'POLYGON', 2, false);

Which means 2D polygon in WGS84.

Then I inserted a new polygon into specific row by:

UPDATE table_name
SET column_name = ST_MakePolygon(ST_GeomFromText('LINESTRING(lon1 lat1, lon2 lat2 ... lon1 lat1)'))
WHERE gid=26;

The result is "violates check constraint enforce_srid" error. What am I doing wrong?

  • 2
    You didn't specify the SRID parameter in ST_GeomFromText, which is basically what the error message said. – Vince Jul 16 '16 at 1:57
  • Where I need to specify? In the new column I wrote the 4326 – michael Jul 16 '16 at 1:58
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    Look at the documentation. You need to specify an SRID in every ST_GeomFromText or it will use 0, which violates the constraint. Do you realize you're wasting time by generating a line from WKT then converting to polygon when you could just generate a polygon in one step? – Vince Jul 16 '16 at 2:43
  • How can I generate polygon in one step? – michael Jul 16 '16 at 13:19
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You created a geometry colum with SRID 4326 but then you are trying to put in a polygon that does not identify an SRID. You just need to pass the polygon to ST_SetSRID() like this:

UPDATE table_name
SET column_name = ST_SetSRID(ST_MakePolygon(ST_GeomFromText('LINESTRING(lon1 lat1, lon2 lat2 ... lon1 lat1)')),4326)
WHERE gid=26;

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