Oracle设置主键自增长

第一步：为表设置主键

第二步：新建序列

CREATE SEQUENCE SQ.SEQ_INCREASE
  START WITH 12
  MAXVALUE 999
  MINVALUE 0

  INCREMENT BY 1
  NOCYCLE
  NOCACHE
  NOORDER;

第三步：创建触发器

CREATE OR REPLACE TRIGGER SQ.tg_depid_increase
BEFORE INSERT
ON SQ.SYS_DEPARTMENT //表名
REFERENCING NEW AS New OLD AS Old
FOR EACH ROW
WHEN (
New.id is null
      )
BEGIN
select seq_increase.nextval into :New.id from dual;
END tg_depid_increase;