Question

我有两张桌子 - Transaction和TransactionEntry。 Transaction包含时间，TransactionEntry包含已售出的商品。

一个Transaction可以有多个TransactionEntry

我希望在2个日期内找到所有TransactionEntry.ItemID＆并且TransactionEntry.Quantity。然后GROUP BY TransactionEntry.ItemID。

此代码的工作原理并给出了预期的结果：

SELECT TransactionEntry.ItemID AS iID, SUM(TransactionEntry.Quantity)
FROM Transaction INNER JOIN TransactionEntry ON TransactionEntry.TransactionNumber = Transaction.TransactionNumber
WHERE Transaction.Time > '2015-07-27 00:00:00' AND Transaction.Time < '2015-08-02 23:59:59'
GROUP BY TransactionEntry.ItemID
ORDER BY SUM(TransactionEntry.Quantity) DESC

不知道如何创建一个表，所以我画了一个例子哈哈：

 -----------------
| iID   | SUM(T.. |
|-----------------| 
| 30419 | 58      |
| 30420 | 50      |
| 55416 | 36      |
| ...   | ...     |
 -----------------

我的问题是我想要第3列，它告诉我有多少交易构成了SUM。使用上面的例子，iID 30419卖了58次，但可能是58个不同的人或只有1个人。我想知道这一点。

以下SQL有效：

SELECT COUNT(TransactionEntry.ID) 
FROM Transaction INNER JOIN TransactionEntry ON TransactionEntry.TransactionNumber = Transaction.TransactionNumber 
WHERE Transaction.Time > '2015-07-27 00:00:00' AND Transaction.Time < '2015-08-02 23:59:59' AND TransactionEntry.ItemID = 10791

但我不确定如何合并2，如果这是有道理的。

我尝试了以下内容，但它超时了：

SELECT TransactionEntry.ItemID AS iID, SUM(TransactionEntry.Quantity), (SELECT COUNT(TransactionEntry.ID) FROM Transaction INNER JOIN TransactionEntry ON TransactionEntry.TransactionNumber = Transaction.TransactionNumber WHERE Transaction.Time > '2015-07-27 00:00:00' AND Transaction.Time < '2015-08-02 23:59:59' AND TransactionEntry.ItemID = iID) AS C
FROM Transaction INNER JOIN TransactionEntry ON TransactionEntry.TransactionNumber = Transaction.TransactionNumber
WHERE Transaction.Time > '2015-07-27 00:00:00' AND Transaction.Time < '2015-08-02 23:59:59'
GROUP BY TransactionEntry.ItemID
ORDER BY SUM(TransactionEntry.Quantity) DESC

我可以追求的是什么？

由于

Answer 1

你能试试这个：

SELECT T.ItemID
    , SUM(TE.Quantity)
    , COUNT(TE.ID) 
    FROM Transaction T
    INNER JOIN TransactionEntry TE ON TE.TransactionNumber = T.TransactionNumber
    WHERE T.Time BETWEEN '2015-07-27 00:00:00' AND '2015-08-02 23:59:59'
    GROUP BY T.ItemID

mySQL - 同一行上的Count和SUM

1 个答案: