create or replace trigger TR_tbl_b
before INSERT OR UPDATE ON tbl FOR EACH ROW
DECLARE
BEGIN
:New.Col1 := replace(REPLACE(:New.col1,' ',''),',','') ;
:New.Col2 := replace(REPLACE(:New.col2,' ',''),',','') ;
:New.Col3 := replace(REPLACE(:New.col3,' ',''),',','') ;
END;