Re: Trigger Problem

Peter Lancashire wrote: > Ileana Soler wrote: > > > > A table named "tab1" have the following structure: > > create table tab1 ( > > a integer primary key constraint num, > > b integer, > > c integer)> > The field named "c" will have the result of a+b. > > I want to fill "c" in a trigger on insert on "tab1", but I can't because > > there are the following rule in Informix: "You cannot reference the > > triggering table in any triggered SQL statement with some exceptions". > > I can fill "c" in a trigger on update, but not on insert (error 747). > > My question is: How can I fullfill calculated fields in tables in Informix > > using triggers or stored procedures calling by triggers? > An alternative would be a view: > > CREATE VIEW view1 (a, b, c) AS > SELECT a, b, a + b FROM tab1;> > Having column c in your base table means that your database is not in > third normal form. Is that what you want? Or, migrate to 7.3 - it supposedly removes the restriction that insert triggers cannot modify the triggering table. Roger Tomas AG Communication Systems