【搞不明白】redis和mysql、mybatisplus有啥关系

news2024/12/29 4:06:02

一个解决三天的bug，到现在也没有搞明白，如题，到底redis和mysql、mybatisplus能有啥关系。三个不相关的嘛

记录下问题： (框架用的Jeecgboot 3.6.0) – 学习使用
看下面的一段代码，是一个分页查询：注意引用的redisTemplate对象，它定义成立RedisTemplate ,没加任何泛型

controller：

	@Autowired
	private IDeviceRandomRecordService deviceRandomRecordService;
	@Autowired
	private RedisTemplate redisTemplate;

	/**
	 * 分页列表查询
	 *
	 * @param deviceRandomRecord
	 * @param pageNo
	 * @param pageSize
	 * @param req
	 * @return
	 */
	@ApiOperation(value="设备随机数生成记录表-分页列表查询", notes="设备随机数生成记录表-分页列表查询")
	@GetMapping(value = "/list")
	public Result<IPage<DeviceRandomRecord>> queryPageList(DeviceRandomRecord deviceRandomRecord,
								   @RequestParam(name="pageNo", defaultValue="1") Integer pageNo,
								   @RequestParam(name="pageSize", defaultValue="10") Integer pageSize,
								   HttpServletRequest req) {
		Set<String> keys = redisTemplate.keys(DeviceCommonConstant.DEVICE_RANDOM_CODE + "*");// 查询所有在线设备id的key
		List<String> codes = redisTemplate.opsForValue().multiGet(keys);// 查询所有在线设备的shakeCode
		// .... 此处省略不必要的判断操作
		Page<DeviceRandomRecord> page = new Page<DeviceRandomRecord>(pageNo, pageSize);
		IPage<DeviceRandomRecord> pageList = deviceRandomRecordService.pageDeviceRandomRecord(page, deviceRandomRecord);
		List<DeviceRandomRecord> list = pageList.getRecords();
		if (ObjectUtils.isNotEmpty(list)) {
			if (deviceRandomRecord.getIsOnline()) {
				for (DeviceRandomRecord randomRecord : list) {
					randomRecord.setIsOnline(true);// 在线
				}
			} else {
				for (DeviceRandomRecord randomRecord : list) {
					randomRecord.setIsOnline(false);// 离线
				}
			}
		}
		return Result.OK(pageList);
	}

上述代码中，首先通过redis查询在线的设备的shakeCode列表，有了codes 信息后在通过mybatisplus插件去查询mysql数据库。我把mapper的xml文件也贴出来，如下：

    <resultMap id="DeviceRandomRecordMap" type="org.jeecg.modules.device.entity.DeviceRandomRecord">
        <result column="id" property="id" jdbcType="VARCHAR"/>
        <result column="create_by" property="createBy" jdbcType="VARCHAR"/>
        <!-- .... 省略字段 --> 
    </resultMap>
    <select id="pageDeviceRandomRecord" resultMap="DeviceRandomRecordMap">
        SELECT
        DeviceRandomRecord.*, device.device_name as deviceName
        from device_random_record as DeviceRandomRecord left join device on DeviceRandomRecord.device_id=device.device_code
        where 1=1
        <if test="query.deviceName!=null and query.deviceName!=''">
            and device.device_name like CONCAT('%', #{query.deviceName}, '%')
        </if>
        <if test="query.isOnline!=null and query.isOnline==true">
            and DeviceRandomRecord.shake_code in
            <foreach item="code" collection="query.onlineCodes" open="(" separator="," close=")">
                #{code}
            </foreach>
        </if>
        <if test="query.isOnline!=null and query.isOnline==false">
            and DeviceRandomRecord.shake_code not in
            <foreach item="code" collection="query.offlineCodes" open="(" separator="," close=")">
                #{code}
            </foreach>
        </if>
        <!-- .... 省略其他查询条件的构建 --> 
		order by DeviceRandomRecord.create_time desc,DeviceRandomRecord.id
    </select>

上面的过程看似标准的分页查询，正常可以得到结果：
正常获取分页查询结果
好嘛，为了代码显得格式规范，我把代码格式化，将漏掉的泛型添加上去后，controller代码如下：

@Autowired
	private IDeviceRandomRecordService deviceRandomRecordService;
	@Autowired
	private RedisTemplate<String, String> redisTemplate;

	/**
	 * 分页列表查询
	 *
	 * @param deviceRandomRecord
	 * @param pageNo
	 * @param pageSize
	 * @param req
	 * @return
	 */
	@ApiOperation(value="设备随机数生成记录表-分页列表查询", notes="设备随机数生成记录表-分页列表查询")
	@GetMapping(value = "/list")
	public Result<IPage<DeviceRandomRecord>> queryPageList(DeviceRandomRecord deviceRandomRecord,
								   @RequestParam(name="pageNo", defaultValue="1") Integer pageNo,
								   @RequestParam(name="pageSize", defaultValue="10") Integer pageSize,
								   HttpServletRequest req) {
		Set<String> keys = redisTemplate.keys(DeviceCommonConstant.DEVICE_RANDOM_CODE + "*");// 查询所有在线设备id的key
		List<String> codes = redisTemplate.opsForValue().multiGet(keys);// 查询所有在线设备的shakeCode
		// .... 此处省略不必要的判断操作
		Page<DeviceRandomRecord> page = new Page<DeviceRandomRecord>(pageNo, pageSize);
		IPage<DeviceRandomRecord> pageList = deviceRandomRecordService.pageDeviceRandomRecord(page, deviceRandomRecord);
		List<DeviceRandomRecord> list = pageList.getRecords();
		if (ObjectUtils.isNotEmpty(list)) {
			if (deviceRandomRecord.getIsOnline()) {
				for (DeviceRandomRecord randomRecord : list) {
					randomRecord.setIsOnline(true);// 在线
				}
			} else {
				for (DeviceRandomRecord randomRecord : list) {
					randomRecord.setIsOnline(false);// 离线
				}
			}
		}
		return Result.OK(pageList);
	}

注意，只改动了这里

@Autowired
private RedisTemplate<String, String> redisTemplate;

将RedisTemplate添加了泛型，因为查询分页的方法里面所有的操作都是对字符串的，当然也尝试过

@Autowired
private StringRedisTemplate redisTemplate;

问题，就出现了，同样的条件，数据就查询不出来了：
同样条件查不出数据了
简直离谱，毫无道理可言！
这个bug跟踪了三天没有理出个头绪来，redis、mysql、mybatisplus能有什么关系？框架中的东西就是简单的查询操作，redis中获取的数据只是一个查询的条件变量，简直离谱！！！

去掉泛型后，就有结果，加上后，mybatisplus只能打印出 count语句，并且count是有结果的，就是不执行select查询数据操作：

2024-03-27 22:13:17.362 [http-nio-8080-exec-2] [39mDEBUG[0;39m [36mo.j.m.d.m.D.pageDeviceRandomRecord_mpCount:137[0;39m - ==>  Preparing: SELECT COUNT(*) AS total FROM device_random_record AS DeviceRandomRecord WHERE 1 = 1 AND DeviceRandomRecord.shake_code IN (?, ?)
2024-03-27 22:13:17.363 [http-nio-8080-exec-2] [39mDEBUG[0;39m [36mo.j.m.d.m.D.pageDeviceRandomRecord_mpCount:137[0;39m - ==> Parameters: "318812"(String), "320221"(String)
2024-03-27 22:13:17.366 [http-nio-8080-exec-2] [39mDEBUG[0;39m [36mo.j.m.d.m.D.pageDeviceRandomRecord_mpCount:137[0;39m - <==      Total: 1

实际上mysql数据库中的数据都嘎嘎存在：

2024-03-27 22:22:59.451 [http-nio-8080-exec-1] [39mDEBUG[0;39m [36mo.j.m.d.m.D.pageDeviceRandomRecord_mpCount:137[0;39m - ==>  Preparing: SELECT COUNT(*) AS total FROM device_random_record AS DeviceRandomRecord WHERE 1 = 1 AND DeviceRandomRecord.shake_code IN (?, ?)
2024-03-27 22:22:59.515 [http-nio-8080-exec-1] [39mDEBUG[0;39m [36mo.j.m.d.m.D.pageDeviceRandomRecord_mpCount:137[0;39m - ==> Parameters: 318812(String), 320221(String)
2024-03-27 22:22:59.530 [http-nio-8080-exec-1] [39mDEBUG[0;39m [36mo.j.m.d.m.D.pageDeviceRandomRecord_mpCount:137[0;39m - <==      Total: 1
2024-03-27 22:22:59.536 [http-nio-8080-exec-1] [39mDEBUG[0;39m [36mo.j.m.d.m.D.pageDeviceRandomRecord:137[0;39m - ==>  Preparing: SELECT DeviceRandomRecord.id, DeviceRandomRecord.create_by, DeviceRandomRecord.create_time, DeviceRandomRecord.update_by, DeviceRandomRecord.update_time, DeviceRandomRecord.sys_org_code, DeviceRandomRecord.shake_code, DeviceRandomRecord.device_id, DeviceRandomRecord.port, DeviceRandomRecord.dest_port, DeviceRandomRecord.cur_day, DeviceRandomRecord.ip_addr, DeviceRandomRecord.conn_duration, DeviceRandomRecord.offline_time, device.device_name AS deviceName FROM device_random_record AS DeviceRandomRecord LEFT JOIN device ON DeviceRandomRecord.device_id = device.device_code WHERE 1 = 1 AND DeviceRandomRecord.shake_code IN (?, ?) ORDER BY DeviceRandomRecord.create_time DESC, DeviceRandomRecord.id LIMIT ?
2024-03-27 22:22:59.544 [http-nio-8080-exec-1] [39mDEBUG[0;39m [36mo.j.m.d.m.D.pageDeviceRandomRecord:137[0;39m - ==> Parameters: 318812(String), 320221(String), 10(Long)
2024-03-27 22:22:59.551 [http-nio-8080-exec-1] [39mDEBUG[0;39m [36mo.j.m.d.m.D.pageDeviceRandomRecord:137[0;39m - <==      Total: 2