有沒有辦法來總結行的值？

Question

我有一個SQL查詢，其中IM使用SUM：

SELECT 
    SUM(CASE WHEN `ID_Event1` != 0 THEN 1 ELSE 0 END) AS count1, 
    SUM(CASE WHEN `ID_Event2` != 0 THEN 1 ELSE 0 END) AS count2, 
    SUM(CASE WHEN `ID_Event3` != 0 THEN 1 ELSE 0 END) AS count3, 
    SUM(CASE WHEN `ID_Event4` != 0 THEN 1 ELSE 0 END) AS count4, 
    SUM(CASE WHEN `ID_Event5` != 0 THEN 1 ELSE 0 END) AS count5 
FROM `ec_calendar` WHERE Year(`Day`)=2015 AND Month(`Day`)=6 

結果是：

但我想SUM這些colums。預期結果是（3 + 4 + 3 + 3 + 4）。

有沒有解決方法？

Answer 1

然後使用+：

SELECT (SUM(CASE WHEN `ID_Event1` != 0 THEN 1 ELSE 0 END) + 
     SUM(CASE WHEN `ID_Event2` != 0 THEN 1 ELSE 0 END) + 
     SUM(CASE WHEN `ID_Event3` != 0 THEN 1 ELSE 0 END) + 
     SUM(CASE WHEN `ID_Event4` != 0 THEN 1 ELSE 0 END) + 
     SUM(CASE WHEN `ID_Event5` != 0 THEN 1 ELSE 0 END) 
     ) as cnt 
FROM `ec_calendar` 
WHERE day >= '2015-06-01' and day < '2015-07-01' 

注意，我改變了WHERE條款。如果您的索引號爲day，則此方法效率更高。

的MySQL把布爾爲整數，所以你可以寫爲：

SELECT (SUM(ID_Event1 <> 0) + SUM(ID_Event2 <> 0) + 
     SUM(ID_Event3 <> 0) + SUM(ID_Event4 <> 0) + 
     SUM(ID_Event5 <> 0) 
     ) as cnt 
FROM `ec_calendar` 
WHERE day >= '2015-06-01' and day < '2015-07-01' 

Answer 2

您可以添加計算的列。

SELECT 
SUM(CASE WHEN `ID_Event1` != 0 THEN 1 ELSE 0 END) AS count1, 
SUM(CASE WHEN `ID_Event2` != 0 THEN 1 ELSE 0 END) AS count2, 
SUM(CASE WHEN `ID_Event3` != 0 THEN 1 ELSE 0 END) AS count3, 
SUM(CASE WHEN `ID_Event4` != 0 THEN 1 ELSE 0 END) AS count4, 
SUM(CASE WHEN `ID_Event5` != 0 THEN 1 ELSE 0 END) AS count5, 
SUM(CASE WHEN `ID_Event1` != 0 THEN 1 ELSE 0 END)+ 
SUM(CASE WHEN `ID_Event2` != 0 THEN 1 ELSE 0 END)+ 
SUM(CASE WHEN `ID_Event3` != 0 THEN 1 ELSE 0 END)+ 
SUM(CASE WHEN `ID_Event4` != 0 THEN 1 ELSE 0 END)+ 
SUM(CASE WHEN `ID_Event5` != 0 THEN 1 ELSE 0 END) as total 
FROM `ec_calendar` WHERE Year(`Day`)=2015 AND Month(`Day`)=6