Mysql , 作为验证值的平均值（NO2） 来自nabelvalidated_pay 其中定时>1360236120000且定时

更改后，您将获得两行已验证读数和一行未验证读数。您使用的最后一组将对这两行进行分组，以获得验证读数。由于在select like max（mergedData.rawValue）中使用聚合函数，因此将获得所需的结果。

好的，这似乎可行。但是，已验证的数据仍然显示在原始数据列中。你知道为什么吗？

+-----------------+---------------------+--------------+
+ PK [bigint(20)] +  timed [bigint(20)] + NO2 [double] +
+-----------------+---------------------+--------------+

SELECT  
    mergedData.rawValue,
    mergedData.validatedValue,
    CAST(IF(mergedData.validatedValue IS NULL, mergedData.rawValue, mergedData.validatedValue) AS DECIMAL(65, 2)) as sensorValue,
    timeValue,
    IsValid
FROM
(SELECT 
    Month(FROM_UNIXTIME(timed / 1000)) as months,
    Year(FROM_UNIXTIME(timed / 1000)) as years,
    DAYOFMONTH(FROM_UNIXTIME(timed / 1000)) as days,
    HOUR(FROM_UNIXTIME(timed / 1000)) as hours,
    MINUTE(FROM_UNIXTIME(timed / 1000)) as minutes,
    avg(NO2) as rawValue,
    FROM_UNIXTIME(timed / 1000) as timeValue,
    IF(NO2 IS NOT NULL, 1, 0) as IsValid,
    NULL as validatedValue
FROM
    nabelnrt_pay
WHERE
    timed > 1360236120000
    AND timed < 1391772120000
GROUP BY years, months, days
UNION
SELECT 
    Month(FROM_UNIXTIME(timed / 1000)) as months,
    Year(FROM_UNIXTIME(timed / 1000)) as years,
    DAYOFMONTH(FROM_UNIXTIME(timed / 1000)) as days,
    HOUR(FROM_UNIXTIME(timed / 1000)) as hours,
    MINUTE(FROM_UNIXTIME(timed / 1000)) as minutes,
    avg(NO2) as validatedValue,
    FROM_UNIXTIME(timed / 1000) as timeValue,
    IF(NO2 IS NOT NULL, 1, 0) as IsValid,
    NULL as rawValue
FROM
    nabelvalidated_pay
WHERE
    timed > 1360236120000
    AND timed < 1391772120000
GROUP BY years, months, days) as mergedData ORDER BY timeValue

SELECT max(mergedData.rawValue),
       max(mergedData.validatedValue),
       CAST(IF(mergedData.validatedValue IS NULL, mergedData.rawValue, mergedData.validatedValue) AS DECIMAL(65, 2)) as sensorValue,
       timeValue,
       IsValid
FROM ((SELECT Month(FROM_UNIXTIME(timed / 1000)) as months,
              Year(FROM_UNIXTIME(timed / 1000)) as years,
              DAYOFMONTH(FROM_UNIXTIME(timed / 1000)) as days,
              HOUR(FROM_UNIXTIME(timed / 1000)) as hours,
              MINUTE(FROM_UNIXTIME(timed / 1000)) as minutes,
              avg(NO2) as rawValue,
              FROM_UNIXTIME(timed / 1000) as timeValue,
              IF(NO2 IS NOT NULL, 1, 0) as IsValid,
              NULL as validatedValue
      FROM nabelnrt_pay
      WHERE timed > 1360236120000 AND timed < 1391772120000
      GROUP BY years, months, days
     )
     UNION ALL
     (SELECT Month(FROM_UNIXTIME(timed / 1000)) as months,
             Year(FROM_UNIXTIME(timed / 1000)) as years,
             DAYOFMONTH(FROM_UNIXTIME(timed / 1000)) as days,
             HOUR(FROM_UNIXTIME(timed / 1000)) as hours,
             MINUTE(FROM_UNIXTIME(timed / 1000)) as minutes,
             avg(NO2) as validatedValue,
             FROM_UNIXTIME(timed / 1000) as timeValue,
             IF(NO2 IS NOT NULL, 1, 0) as IsValid,
             NULL as rawValue
      FROM nabelvalidated_pay
      WHERE timed > 1360236120000 AND timed < 1391772120000
      GROUP BY years, months, days
     )
    ) as mergedData
GROUP BY years, months, days
ORDER BY timeValue

SELECT max(mergedData.rawValue),
       max(mergedData.validatedValue),
       CAST(IF(max(mergedData.validatedValue) IS NULL, max(mergedData.rawValue),  
       max(mergedData.validatedValue)) AS DECIMAL(65, 2)) as sensorValue,
       max(timeValue),
       max(IsValid)  
FROM ((SELECT Month(FROM_UNIXTIME(timed / 1000)) as months,
          Year(FROM_UNIXTIME(timed / 1000)) as years,
          DAYOFMONTH(FROM_UNIXTIME(timed / 1000)) as days,
          HOUR(FROM_UNIXTIME(timed / 1000)) as hours,
          MINUTE(FROM_UNIXTIME(timed / 1000)) as minutes,
          avg(NO2) as rawValue,
          FROM_UNIXTIME(timed / 1000) as timeValue,
          0 IsValid,
          NULL as validatedValue
  FROM nabelnrt_pay
  WHERE timed > 1360236120000 AND timed < 1391772120000
  GROUP BY years, months, days
 )
 UNION ALL
 (SELECT Month(FROM_UNIXTIME(timed / 1000)) as months,
         Year(FROM_UNIXTIME(timed / 1000)) as years,
         DAYOFMONTH(FROM_UNIXTIME(timed / 1000)) as days,
         HOUR(FROM_UNIXTIME(timed / 1000)) as hours,
         MINUTE(FROM_UNIXTIME(timed / 1000)) as minutes,
         NULL as rawValue,
         FROM_UNIXTIME(timed / 1000) as timeValue,
         1 AS IsValid,
         avg(NO2) as validatedValue
  FROM nabelvalidated_pay
  WHERE timed > 1360236120000 AND timed < 1391772120000
  GROUP BY years, months, days
 )
) as mergedData
GROUP BY years, months, days
ORDER BY timeValue