Trigger on a column

Hi,

My trigger's running on a table that works perfectly. This trigger calls 
a function that inserts or modifies a row of a different table. My 
problem is that I need to optimize this trigger, and the only way that 
I've found is to fire the trigger  when certain table fields are 
modified.  I do it like this:

CREATE TRIGGER tr_barra_aps AFTER INSERT OR DELETE OR UPDATE OF status   ON am_access_point EXECUTE PROCEDURE
f_barra_aps();

but I get this error:
ERROR:  syntax error at or near "status" at character 62

The status field is correct. Can anybody help me?

Thanks

-- 
Josep Sanmarti
Analista de Projectes

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