測試表：

CREATE TABLE UserInfo(
id NUMBER(10) NOT NULL,
username VARCHAR2(15) NOT NULL,
CONSTRAINTS PF_UserInfo PRIMARY KEY(Id)
);

方法一：顯示呼叫序列的下一個值插入：

SQL語句：

-- 建立序列
CREATE SEQUENCE Tab_UserInfo_Sequence
START WITH 1
MINVALUE 1
MAXVALUE 999999999
INCREMENT BY 1
CACHE 20;

INSERT INTO USERINFO values(Tab_UserInfo_Sequence.
 
nextval,'aaa');
INSERT INTO USERINFO values(Tab_UserInfo_Sequence.nextval,'bbb');
SELECT * FROM UserInfo;

結果：

方法二：序列+觸發器：

SQL語句：

CREATE SEQUENCE Tab_UserInfo_Sequence
START WITH 1
MINVALUE 1
MAXVALUE 999999999
INCREMENT BY 1
CACHE 20;

DROP TRIGGER Tig_UserInfo_Insert;
CREATE TRIGGER Tig_UserInfo_Insert
BEFORE INSERT
 
 
ON UserInfo
FOR EACH ROW
BEGIN 
	 SELECT Tab_UserInfo_Sequence.nextval into :new.id FROM dual;
END;

INSERT INTO UserInfo(username) values('zs');
INSERT INTO UserInfo(username) values('ls');
SELECT * FROM UserInfo;

結果：