db2数据库 序列和触发器的问题

CREATE SEQUENCE SEQtbCaPolicy INCREMENT BY 1 START WITH 1
MAXVALUE 1.0E28 MINVALUE 1 NOCYCLE
CACHE 20 NOORDER;

CREATE OR REPLACE TRIGGER TRItbCaPolicyID
BEFORE INSERT ON tbCaPolicy
for each row
begin select SEQtbCaPolicy.nextval into :new.iID from dual;
end;

以上是oracle数据库的实现，我想问下在db2 中如何实现select SEQtbCaPolicy.nextval into :new.iID from dual，请各位帮帮忙，谢谢。。。。