MyBatis 获取 insert 插入数据的主键值（MySQL）

方法一

<insert id="insertNewOrder" parameterType="Order"  
        useGeneratedKeys="true" keyProperty="id">
    insert into orders (user_id, status, create_time)
    values(#{userId}, 0, sysdate())
</insert>

useGeneratedKeys=“true” 也可以写在注释中：

@Options(useGeneratedKeys = true)
int insertNewOrder(Order order);

方法二

<insert id="insertNewOrder" parameterType="Order">
    <!-- selectKey将主键返回，需要再返回 -->
    <selectKey keyProperty="id" order="AFTER" resultType="java.lang.Integer">
        select LAST_INSERT_ID()
    </selectKey>
    insert into orders (user_id, status, create_time)
    values(#{userId}, 0, sysdate())
</insert>

接收数据

Order o = new Order();
o.setUserId(2);
int n = oMapper.insertNewOrder(o);
System.out.println("刚刚插入的主键："+o.getId());