复杂SQL查询JOIN和其中

我有一个表，我需要从中获取联系人。因此，我使用一个复杂的查询从我的“短信”表中检索所有联系人。复杂SQL查询JOIN和其中

但是，它应该只计算提供的“imei”字段的记录，但我的查询会一直返回特定联系人的所有计数。

下面是代码是用的，有什么建议吗？

$sql = $this->db->query(' 
    SELECT 
     t1.mnumber AS t1_number, t1.mcontent AS t1_content, t1.mcontact as t1_contact, SUM(t2.TOTAL) AS mTotal 
    FROM 
     sms t1 
      JOIN 
     (SELECT 
      mContent, mcontact, COUNT(mNumber) AS TOTAL, mnumber, MAX(mID) mID 
     FROM 
      sms 
     GROUP BY mContact) t2 ON t1.mcontact = t2.mcontact 
      AND t1.mid = t2.mid 
     WHERE t1.mIMEI = ' . (IMEI) . ' 
     GROUP BY t1.mContact 
     ORDER BY t1.mid DESC'); 

    return $sql->result();

谢谢你!!

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2013-05-09 De ruige

当没有指定组中的“SELECT”列表中的所有列时，请注意在MySQL中使用“GROUP BY”。你的结果可能是不确定的...... – 2013-05-09 15:24:41

你的'WHERE'子句在内部子查询执行其计数之后被评估**。 – 2013-05-09 15:36:05

更好的格式化，查询是：

SELECT t1.mnumber AS t1_number, t1.mcontent AS t1_content, t1.mcontact as t1_contact, SUM(t2.TOTAL) AS mTotal 
FROM sms t1 JOIN 
    (SELECT mContent, mcontact, COUNT(mNumber) AS TOTAL, mnumber, MAX(mID) mID 
     FROM sms 
     GROUP BY mContact 
    ) t2 
    ON t1.mcontact = t2.mcontact AND t1.mid = t2.mid 
WHERE t1.mIMEI = ' . (IMEI) . ' 
GROUP BY t1.mContact 
ORDER BY t1.mid DESC

的问题是，where条款是放错了地方。为了影响计数，你需要在子查询中使用它。为了影响输出行，您需要在外部查询中使用它。我建议：

SELECT t1.mnumber AS t1_number, t1.mcontent AS t1_content, t1.mcontact as t1_contact, SUM(t2.TOTAL) AS mTotal 
FROM sms t1 JOIN 
    (SELECT mContent, mcontact, COUNT(mNumber) AS TOTAL, mnumber, MAX(mID) as maxmid 
     FROM sms 
     WHERE sms.mIMEI = ' . (IMEI) . ' 
     GROUP BY mContact 
    ) t2 
    ON t1.mcontact = t2.mcontact AND t1.mid = t2.maxmid 
GROUP BY t1.mContact 
ORDER BY t1.mid DESC

我怀疑可能还有其他的简化，这取决于mid和mcontact指的是在数据库结构方面。

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2013-05-09 15:32:47

谢谢，我注意到:)但是，它仍然给我在返回错误的计数。例如，对于IMEI 0123，联系X的计数是12.在一般表中，X的总计数是40.当我执行我的查询时，结果是40而不是12. – 2013-05-09 15:39:38

@SamNapkins：谢谢，但仍然一样问题？ – 2013-05-10 01:22:59

在SELECT语句中都需要WHERE子句。

SELECT t1.mnumber AS t1_number, t1.mcontent AS t1_content, t1.mcontact as t1_contact, SUM(t2.TOTAL) AS mTotal 
FROM sms t1 JOIN 
    (SELECT mContent, mcontact, COUNT(mNumber) AS TOTAL, mnumber, MAX(mID) mID 
     FROM sms 
     WHERE mIMEI = ' . (IMEI) . ' 
     GROUP BY mContact 
    ) t2 
    ON t1.mcontact = t2.mcontact AND t1.mid = t2.mid 
WHERE t1.mIMEI = ' . (IMEI) . ' 
GROUP BY t1.mContact 
ORDER BY t1.mid DESC

没有在这两个地方的WHERE条款，你将加入匹配mContact的所有记录。即使那些不符合你的t1.mIMEI = ' . (IMEI) . '条件。

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2013-05-09 17:41:14 SamNapkins

@Gordon Linoff给出的答案是正确的。真正的问题在于表格本身。

它存储所有消息，但有时'mNumber'是国际电话号码，有时它是用户将其存储到手机的格式。

因此，当我使用'mNumber'字段加载'mContent'时，它只会给我一个部分结果！

那么仍然在寻找解决方案呢？也许是多个WHERE clausule？

来源

2013-05-10 10:45:59

复杂SQL查询JOIN和其中

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