sequence 的使用方法

create sequence seq_2
increment by 1
start with 1
maxvalue 100
minvalue  0
cycle
cache 100
order;

CREATE TABLE tab1 (col1 int, col2 int);
INSERT INTO tab1 VALUES (0, 0);
INSERT INTO tab1 (col1, col2) VALUES (seq_2.NEXTVAL, seq_2.NEXTVAL);