选择不同的WHERE条件

我想运行一个像这样的选择。选择不同的WHERE条件

SELECT 
     COUNT(*) WHERE switch=0 AND detail=1 AS zeroone 
    AND 
     COUNT(*) WHERE switch=0 AND detail=2 AS zerotwo 
    AND 
     COUNT(*) WHERE switch=1 AND detail=1 AS oneone 
    AND 
     COUNT(*) WHERE swithc=1 AND detail=2 AS onetwo 
    FROM tablename

有没有办法做到这一点？

来源

2012-07-31 steventnorris

您可以使用CASE声明在SELECT得到的结果：

SELECT SUM(case when switch=0 AND detail=1 then 1 else 0 end) as zeroone 
    , SUM(case when switch=0 AND detail=2 then 1 else 0 end) as zerotwo 
    , SUM(case when switch=1 AND detail=1 then 1 else 0 end) as oneone 
    , SUM(case when switch=1 AND detail=2 then 1 else 0 end) as onetw 
FROM tablename

来源

2012-07-31 17:42:37 Taryn

SELECT SUM(CASE WHEN switch = 0 and detail = 1 THEN 1 ELSE NULL END) AS zeroone 
    , ... 
FROM TableName

来源

2012-07-31 17:39:54

SELECT 
    sum(switch=0 AND detail=1) AS zeroone, 
    sum(switch=0 AND detail=2) AS zerotwo, 
    sum(switch=1 AND detail=1) AS oneone, 
    sum(switch=1 AND detail=2) AS onetwo 
FROM tablename

来源

2012-07-31 17:41:49

目前尚不清楚你想要什么。

我想你想一个选择，即返回一行，有4列：

SELECT 
COUNT(*) WHERE switch=0 AND detail=1 AS zeroone, 
COUNT(*) WHERE switch=0 AND detail=2 AS zerotwo, 
COUNT(*) WHERE switch=1 AND detail=1 AS oneone, 
COUNT(*) WHERE swithc=1 AND detail=2 AS onetwo 
FROM tablename

来源

2012-07-31 17:43:38 bpgergo

你为什么不使用它？

SELECT COUNT(*) 
    FROM tablename 
GROUP BY switch, detail

来源

2012-07-31 17:46:49 hmmftg

选择不同的WHERE条件

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