oracle創建表(並且實現ID自增)

CREATE TABLE STUDENT
(
ID INT NOT NULL,
NAME VARCHAR2(4000) NOT NULL,
PRIMARY KEY(ID)
)
TABLESPACE MYDB;
 
--創建自增ID，名稱為：表名_字段名_SEQ
CREATE SEQUENCE sTUDENT_ID_SEQ MINVALUE 1 NOMAXVALUE INCREMENT BY 1 START WITH 1 NOCACHE;
 
 
-- 為Insert操作創建觸發器，無需在SQL語句里寫NEXTVAL，名稱為表名_INS_TRG
CREATE OR REPLACE TRIGGER sTUDENT_INS_TRG BEFORE INSERT ON STUDENT FOR EACH ROW WHEN(NEW.ID IS NULL)
BEGIN
SELECT STUDENT_ID_SEQ.NEXTVAL INTO :NEW.ID FROM DUAL;
END;