dropgeometrycolumn(catalog_name character varying, schema_name character varying, table_name character varying, column_name character varying)

DECLARE

    myrec RECORD;

    okay boolean;

    real_schema name;

​

BEGIN

​

    -- Find, check or fix schema_name

    IF ( schema_name != '' ) THEN

        okay = false;

​

        FOR myrec IN SELECT nspname FROM pg_namespace WHERE text(nspname) = schema_name LOOP

            okay := true;

        END LOOP;

​

        IF ( okay <>  true ) THEN

            RAISE NOTICE 'Invalid schema name - using current_schema()';

            SELECT current_schema() into real_schema;

        ELSE

            real_schema = schema_name;

        END IF;

    ELSE

        SELECT current_schema() into real_schema;

    END IF;

​

    -- Find out if the column is in the geometry_columns table

    okay = false;

    FOR myrec IN SELECT * from public.geometry_columns where f_table_schema = text(real_schema) and f_table_name = table_name and f_geometry_column = column_name LOOP

        okay := true;

    END LOOP;

    IF (okay <> true) THEN

        RAISE EXCEPTION 'column not found in geometry_columns table';

        RETURN false;

    END IF;

​

    -- Remove table column

    EXECUTE 'ALTER TABLE ' || quote_ident(real_schema) || '.' ||

        quote_ident(table_name) || ' DROP COLUMN ' ||

        quote_ident(column_name);

​

    RETURN real_schema || '.' || table_name || '.' || column_name ||' effectively removed.';

​

END;