The writing of DB2 trigger and modification of table primary key structure

DROP TRIGGERtr_monthlyclosing;CREATE TRIGGERTr_monthlyclosing NOCASCADEbeforeINSERT  onpt_monthlyclosing referencing NEW asNEWROW forEach ROW MODE db2sqlBEGINATOMICIF(NEWROW. Flowno is NULL) Then        SETNEWROW. Flowno=  CurrentDATE; END IF;ENDALTER TABLEDMS. " Pt_monthlyclosing "DROP CONSTRAINT"Pk_flowno";ALTER TABLEDMS. " Pt_monthlyclosing "ADD CONSTRAINT"Pk_flowno"PRIMARY KEY(flowno,access_date,maintenance_cd,sorting);

The writing of DB2 trigger and modification of table primary key structure