MyBatis入门-update用法

MyBatis中update用法

本篇内容

• update标签的基本用法

实践-更新一条记录

mapper中接口

    /**
     * 根据主键更新
     * @param user 用户记录
     * @return 执行得sql影响得行数
     */
    int updateById(SysUser user);

xml，update标签里，在createTime和headImg两个属性上也可以添加jdbcType的类型

   <!--通过主键修改数据-->
    <update id="updateById">
        update mybatis.sys_user
        <set>
            user_name = #{userName},
            user_password = #{userPassword},
            user_email = #{userEmail},
            user_info = #{userInfo},
            head_img = #{headImg,jdbcType=BLOB},
            create_time = #{createTime,jdbcType=TIMESTAMP},
        </set>
        where id = #{id}
    </update>

测试方法，查询一条记录后修改用户名和用户邮箱，看是否更新成功

public void testUpdateById(){
    
    
        SqlSession sqlSession = getSqlSession();

        try {
    
    
            SysUserMapper mapper = sqlSession.getMapper(SysUserMapper.class);
            //获取数据库中一条记录进行修改
            SysUser user = mapper.queryById(1L);
            Assert.assertEquals("admin",user.getUserName());
            LOGGER.info("用户信息：{}",user.toString());
            // 修改用户名
            user.setUserName("admin_test");
            user.setUserEmail("[email protected]");

            //更新数据，update方法返回值是执行sql影响的行数
            int result = mapper.updateById(user);
            Assert.assertEquals(1,result);
            //查看修改后的数据
            SysUser sysUser = mapper.queryById(1L);
            LOGGER.info("修改后的用户信息：{}",sysUser.toString());
            Assert.assertEquals("admin_test",sysUser.getUserName());
        } finally {
    
    
            //为了不影响其他测试，这里进行回滚
            //由于默认的sqlSessionFactory.openSession()是不自动提交的
            //因此不手动执行commit也不会提交到数据库
            sqlSession.rollback();
            //关闭sqlSession
            sqlSession.close();
        }
    }

执行结果，

==>  Preparing: select id, user_name, user_password, user_email, user_info, head_img, create_time from mybatis.sys_user where id = ? 
==> Parameters: 1(Long)
<==    Columns: id, user_name, user_password, user_email, user_info, head_img, create_time
<==        Row: 1, admin, 123456, admin@mybatis.tk, <<BLOB>>, <<BLOB>>, 2021-01-28 21:57:32.0
<==      Total: 1
用户信息：SysUser{id=1, userName='admin', userPassword='123456', userEmail='[email protected]', userInfo='管理员', headImg=null, createTime=Thu Jan 28 21:57:32 CST 2021}
==>  Preparing: update mybatis.sys_user SET user_name = ?, user_password = ?, user_email = ?, user_info = ?, create_time = ? where id = ? 
==> Parameters: admin_test(String), 123456(String), test@mybatis.tk(String), 管理员(String), 2021-01-28 21:57:32.0(Timestamp), 1(Long)
<==    Updates: 1
==>  Preparing: select id, user_name, user_password, user_email, user_info, head_img, create_time from mybatis.sys_user where id = ? 
==> Parameters: 1(Long)
<==    Columns: id, user_name, user_password, user_email, user_info, head_img, create_time
<==        Row: 1, admin_test, 123456, test@mybatis.tk, <<BLOB>>, <<BLOB>>, 2021-01-28 21:57:32.0
<==      Total: 1
修改后的用户信息：SysUser{id=1, userName='admin_test', userPassword='123456', userEmail='[email protected]', userInfo='管理员', headImg=null, createTime=Thu Jan 28 21:57:32 CST 2021}