Geometry type and create trigger for that in postgresql

Question

I want to create a trigger (before inserting trigger), to check the geometry type weather is point, polygon, line, or multi-polygon. After that, I want to set the color property. How can I do this?

I am using postgresql 9.4. My OS is Windows 10.

Table Name: Test, column(s): geoData and color.

CREATE OR REPLACE FUNCTION trigger_color()
  RETURNS trigger AS
$BODY$
BEGIN
if(st_geometrytype(NEW.geoData) like 'ST_Point') then
       INSERT INTO "Test"("color") VALUES (red);
          NEW.color = 'red';
elseif(st_geometrytype(NEW.geoData) like 'ST_Polygon') then
       -- your logic here, for example: 
          NEW.color = 'green';
elseif(st_geometrytype(NEW.geoData) like 'ST_Linestring') then
       -- your logic here, for example: 
          NEW.color = 'yellow';
elseif(st_geometrytype(NEW.geoData) like 'ST_MultiPolygon') then
    NEW.color = 'blue';
else
    NEW.color = 'black';
end if;
END;
$BODY$
  LANGUAGE plpgsql VOLATILE
  COST 100;
ALTER FUNCTION trigger_color()
  OWNER TO postgres;

It shows me :

ERROR: record "new" has no field "geodata"
SQL state: 42703
Context: SQL statement "SELECT (st_geometrytype(NEW.geoData) like 'ST_Point')"
PL/pgSQL function trigger_color() line 3 at IF

How i can solve this?

Answer 1

In your trigger before function (using plpgsql language), you can try something like:

if (st_geometrytype(NEW.geom) like 'ST_Point') then
        -- your logic here, for example: 
           NEW.color = 'red';
end if;