--删除 sequence

drop sequence SEQ_T_PROJECT_COMMENT 

-- 创建 Create sequence

create sequence SEQ_T_PROJECT_COMMENT

minvalue 1

maxvalue 999999999999999999999999999

start with 1

increment by 1

cache 10;

update T_PROJECT_COMMENT set id=seq_id.nextval ;

 

--查询sequence 的值

 

SELECT SEQ_T_PROJECT_COMMENT.NEXTVAL AS DN_LOG_ID FROM DUAL;

select 序列名.Nextval from dual;--生成并获得下一个序列

create sequence seq_id start with 1000 increment by 1 ;

update t set id=seq_id.nextval ;