mybatis 02之增删改查

续上一篇mybatis的增删改查功能，一起进步吧，不是很能看懂的可以回看第一篇也可以评论区交流指正！

在接口添加申请方法

//    根据ID查询数据
    User getUserById(int id);
//    增加一条数据
    int addUser(User user);
//    修改一条数据
    int updateUser(User user);
//    删除一条数据
    int deleteUser(int id);

在xml里面添加实现方法

</select>
    <select id="getUserById" parameterType="int" resultType="com.yue.pojo.User">
        select * from guoquan_test.wuyuetest where id = #{id}
    </select>
    <insert id="addUser" parameterType="com.yue.pojo.User">
        insert into guoquan_test.wuyuetest(id,name,pwd) value (#{id},#{name},#{pwd});
    </insert>

    <update id="updateUser" parameterType="com.yue.pojo.User">
        update wuyuetest
        set name =#{name},pwd =#{pwd}
        where id = #{id};
    </update>

    <delete id="deleteUser" parameterType="int">
        delete
        from wuyuetest
        where id = #{id};
    </delete>

在test类使用方法测试

//    测试查询单条数据
    @Test
    public void getUserById(){
        SqlSession sqlSession = MybatisUtils.getSqlSession();
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);

        User userById = mapper.getUserById(1);
        System.out.println(userById);

        sqlSession.close();
    }
//    测试插图
    @Test
    public void addUser(){
        SqlSession sqlSession = MybatisUtils.getSqlSession();
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);

        mapper.addUser(new User(5,"yuese","123123"));

        sqlSession.commit();
        sqlSession.close();
    }
//    测试update
    @Test
    public void updateUser(){
        SqlSession sqlSession = MybatisUtils.getSqlSession();
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);

        int vaule = mapper.updateUser(new User(4, "胡歌", "123321"));

        sqlSession.commit();
        sqlSession.close();
    }
    //测试删除
    @Test
    public void delectUser(){
        SqlSession sqlSession = MybatisUtils.getSqlSession();
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);

        mapper.deleteUser(5);

        sqlSession.commit();
        sqlSession.close();
    }
}

注意事项

1、继上一篇mybatis第一个程序，又看不懂的可以回去对照~
2、在增删改时需要提交事务

sqlSession.commit();

3、