Oracle 序列

-- 序列
-- currval:返回sequence的当前值
-- nextval：返回增加sequence的值，然后返回sequence的值

SELECT SEQ_NAME.currval FROM dual;
SELECT SEQ_NAME.nextval FROM dual;

-- 创建序列
CREATE SEQUENCE SEQ_NAME
minvalue 1
maxvalue 999999999999999999999
start with 1000
increment by 1
cache 20;