Te serviría en un caso como:
Código SQL
[-]
CREATE TRIGGER "tgrVerDatArea" FOR TBLCATARE ACTIVE
BEFORE INSERT OR UPDATE POSITION 0
AS
BEGIN
if (new.cvecatare is null) then
exception "CveArea";
if (new.descatare is null) then
exception "NomArea";
insert into otratabla (otrosvalores)
when sqlcode -803 do
exception "CodigoDuplicadoEnOtraTabla";
END
Hasta luego.
