如何合並來自同一表的兩個SQL查詢

Question

我在表中有以下（示例）數據

值，日期，設備

我使用數據進行簡單的SLA計算，即在工作時間內多少次數據低於某個閾值。

目前，我運行以下兩個查詢，如下所示

select count(*), DATE(times) from SLA where device='some-dev' and DATE(times) between '2013-05-01' and '2013-05-31' and TIME(times) between '06:00:00' and '18:00:00' and value <150 group by DATE(times);

select count(*), DATE(times) from SLA where device='some-dev' and DATE(times) between '2013-05-01' and '2013-05-31' and TIME(times) between '06:00:00' and '18:00:00' group by DATE(times);

因此，有兩個查詢，一個查詢沒有值<數字，一個查詢沒有值。

有幾個問題，是否有辦法將它們全部合並到一個查詢中，所以我可以看到總數據點和小於閾值的數據點的計數？ 基本上返回三列，一列帶有計數，一列帶有低於閾值的計數和日期

除此之外，有沒有一種簡單的方法可以告訴mysql在返回數據時忽略周末？

謝謝，

Answer 1

使用UNION運算符。

更新后的查詢將如下所示：

(select count(*), DATE(times) from SLA where device='some-dev' and DATE(times) between '2013-05-01' and '2013-05-31' and TIME(times) between '06:00:00' and '18:00:00' and value <150 group by DATE(times))
UNION
(select count(*), DATE(times) from SLA where device='some-dev' and DATE(times) between '2013-05-01' and '2013-05-31' and TIME(times) between '06:00:00' and '18:00:00' group by DATE(times));

Answer 2

如您所寫，如果需要三列 （兩個計數和一個日期），請使用subselect而不是union：

select 
(select count(*) from SLA where device='some-dev' and DATE(times) = DATE(s.times) and  TIME(times) between '06:00:00' and '18:00:00' and value <150),
count(*), 
DATE(s.times) 
from SLA s
where device='some-dev' and DATE(times) between '2013-05-01' and '2013-05-31' and TIME(times) between '06:00:00' and '18:00:00' group by DATE(times)

我沒有測試上面的查詢，因此可能需要進行一些調整，但是請參見一個簡化的工作示例 。

編輯：剛剛用一個（甚至）更有意義的查詢更新了鏈接的小提琴（一次）。

Answer 3

select count(*), DATE(time) from SLA where (device='some-dev' and DATE(time) between '2013-05-01' and '2013-05-31' and TIME(times) between '06:00:00' and '18:00:00' and value <150 group by DATE(time)) or (device='some-dev' and DATE(times) between '2013-05-01' and '2013-05-31' and TIME(time) between '06:00:00' and '18:00:00' group by DATE(time));

Answer 4

怎么樣：

select count(*), DATE(times) from SLA 
where (device='some-dev' and DATE(times) between '2013-05-01' and '2013-05-31' and TIME(times) between '06:00:00' and '18:00:00' and value <150 group by DATE(times))
or (device='some-dev' and DATE(times) between '2013-05-01' and '2013-05-31' and TIME(times) between '06:00:00' and '18:00:00' group by DATE(times));

Answer 5

我使用的是ms-sql，但大概可以執行以下操作：

select count(*), DATE(times), SUM(CASE WHEN value <150  THEN 1 ELSE 0 END)
from SLA
where device='some-dev'
and DATE(times) between '2013-05-01' and '2013-05-31'
and TIME(times) between '06:00:00' and '18:00:00'
group by DATE(times);

在mysql中。