oracle数据库建立序列使用序列实现主键自增

Posted 2020-10-01 Legolas

2.建立序列

-- Create sequence 
create sequence SEQ_SHIP_IMAGE
minvalue 20
maxvalue 999999999999999999
start with 40
increment by 1
cache 20;

使用序列：

SELECT SEQ_SHIP_IMAGE.Nextval from dual;
insert into ship_image (id,img_path,remark,ship_id) values (SEQ_SHIP_IMAGE.Nextval,‘ship3.jpg‘,‘8‘,‘8‘);

或者

<!-- 对应userDao中的insertUser方法，  -->
   <insert id="insertUser" parameterType="com.dy.entity.User">
        <!-- oracle等不支持id自增长的，可根据其id生成策略，先获取id       
        <selectKey resultType="int" order="BEFORE" keyProperty="id">
              select seq_user_id.nextval as id from dual
        </selectKey>        
        -->   
           insert into user(id, name, password, age, deleteFlag) 
               values(#{id}, #{name}, #{password}, #{age}, #{deleteFlag})
   </insert>