Help needed

Hi everyone,

I have some kind of strange problem. I want to build general parametrized 
trigger for my database. The parameter sent to the trigger contains a column 
name that trigger should be check.  

CREATE OR REPLACE FUNCTION F_T_IU__check() RETURNS trigger AS $$DECLARE    vt VARCHAR;BEGIN
...........................................................        vt:='constant_value_id';        RAISE EXCEPTION
'aaa=%',NEW.vt;
 
.............................................................

The 'vt' variable contains the column name. In the above statement I want that 
NEW.vt to be interpreted as NEW.constant_value_id. It is possible to do this?

Thanks,
Nosy