SQL Server：如何组合来自同一个表的两个选择查询并在列上获取结果

Question

我想在具有 group by 的同一个表上组合两个查询。

这是我的桌子：

 Date#####   |  Value1 |  Value2 |   Value3 | Type
 ------------------------------------------------------
 23/04/2014  |  1,2    |    12,3 |    10    | Green
 23/04/2014  |  11,2   |    3    |   10,3   | Non-Green    
 24/04/2014  |  10,9   |    3    |    11    | Green
 24/04/2014  |  2,3    |    12,3 |    8     | Green
 24/04/2014  |  10     |    1    |    11    | Non-Green
 25/04/2014  |  10     |    2    |   10,8   | Non-Green    
 25/04/2014  |  1,4    |    5    |    12    | Green

这些值为Decimal 类型。计算value1,value2,value3 >= 10。预期结果：

 Date#####   | Green |Non-Green
 ------------------------------
 23/04/2014  |  2    | 2
 24/04/2014  |  3    | 2
 25/04/2014  |  1    | 2

绿色和非绿色的值来自于 value1、value2、value3 的计数 >=10，这是我的第一个查询：

Dim strCommand As String = "SELECT d, LW, cnt FROM(SELECT TOP 7 [date] AS d, [Type] as LW, SUM(CASE WHEN Value1 >= 10 THEN 1 ELSE 0 END + CASE WHEN Value2 >= 10 THEN 1 ELSE 0 END + CASE WHEN Value3 >= 10 THEN 1 ELSE 0 END) AS cnt FROM tbBooth where Type = 'Green' GROUP BY [date],[Type] ORDER BY [date] DESC) x ORDER BY d ASC"

它显示：

 Date#####   | Cnt |Type
 ------------------------
 23/04/2014  |  2    | Green
 24/04/2014  |  3    | Green
 25/04/2014  |  1    | Green

我的第二个查询：

Dim strCommand As String = "SELECT d, LW, cnt FROM(SELECT TOP 7 [date] AS d, [Type] as LW, SUM(CASE WHEN Value1 >= 10 THEN 1 ELSE 0 END + CASE WHEN Value2 >= 10 THEN 1 ELSE 0 END + CASE WHEN Value3 >= 10 THEN 1 ELSE 0 END) AS cnt FROM tbBooth where Type = 'Non-Green' GROUP BY [date],[Type] ORDER BY [date] DESC) x ORDER BY d ASC"

它显示：

 Date#####   | Cnt |Type
 ------------------------
 23/04/2014  |  2    | Non-Green
 24/04/2014  |  2    | Non-Green
 25/04/2014  |  2    | Non-Green

我想将两个查询合并为一个，并获取日期、绿色的结果和非绿色的结果。假设我有很多日期组，我希望它只显示基于ASC 顺序的最后 7 组日期。

有什么办法吗？我尝试查看其他 SO 帖子，例如使用 UNION 或 PIVOT，但我不知道如何在我的代码中实现它。

对不起，我昨天已经发布了这个问题，这是一个预期结果的编辑......

提前谢谢....

Answer 1

SELECT d, 
       sum(CASE WHEN LW = 'Green'     THEN cnt ELSE 0 END) [Green], 
       sum(CASE WHEN LW = 'Non-Green' THEN cnt ELSE 0 END) [Non-Green]
FROM
(
  SELECT [date] AS d, 
  [Type] as LW, 
  CASE WHEN Value1 >= 10 THEN 1 ELSE 0 END +
  CASE WHEN Value2 >= 10 THEN 1 ELSE 0 END + 
  CASE WHEN Value3 >= 10 THEN 1 ELSE 0 END AS cnt,
  DENSE_RANK() over (ORDER BY [date] DESC) dr
  FROM tbBooth 
  WHERE Type in ('Green','Non-Green')
) x 
WHERE dr < 8
GROUP BY d
ORDER BY d ASC

Answer 2

您可以使用两个 case 语句，每个值一个；在这里，我首先在一个公用表表达式中拆分行以简化案例；

WITH cte AS (
  SELECT date, type, value1 value FROM tbBooth UNION ALL
  SELECT date, type, value2 value FROM tbBooth UNION ALL
  SELECT date, type, value3 value FROM tbBooth
)
SELECT date d, 
  SUM(CASE WHEN type='Green'     AND value>=10.0 THEN 1 ELSE 0 END) Green,
  SUM(CASE WHEN type='Non-Green' AND value>=10.0 THEN 1 ELSE 0 END) NonGreen
FROM cte
GROUP BY [date] 
ORDER BY [date] DESC

An SQLfiddle to test with.

Answer 3

试试这个查询，而不是每一列的 case...

Select *
From (
    Select [Date], [Type], COUNT(*) Cnt
    From tbBooth
    UnPivot (Value For Name In ([Value1],[Value2],[Value3])) As UnPvt
    Where Value >= 10
    Group By [Date], [Type]
) As GrpBooth
Pivot (SUM(Cnt) For Type IN ([Green],[Non-Green])) As Pvt

输出是：

Date                    Green       Non-Green
----------------------- ----------- -----------
2014-04-23 00:00:00.000 2           2
2014-04-24 00:00:00.000 3           2
2014-04-25 00:00:00.000 1           2

Answer 4

我已尝试获得您所需的输出。请检查一下。

如果我在这里遗漏了什么，请告诉我，以便我更正。

--Simulated your table
DECLARE @tbl TABLE
(
[DATE] DATETIME,
Value1 FLOAT,
Value2 FLOAT,
Value3 FLOAT,
[Type] VARCHAR(50)
)

--Entered values for testing
INSERT INTO @tbl([DATE], VALUE1, VALUE2, VALUE3, [TYPE]) VALUES('04/23/2014','1.2','12.3 ','10','Green')
INSERT INTO @tbl([DATE], VALUE1, VALUE2, VALUE3, [TYPE]) VALUES('04/23/2014','11.2','3','10.3','Non-Green')
INSERT INTO @tbl([DATE], VALUE1, VALUE2, VALUE3, [TYPE]) VALUES('04/24/2014','10.9','3','11','Green')
INSERT INTO @tbl([DATE], VALUE1, VALUE2, VALUE3, [TYPE]) VALUES('04/24/2014','2.3','12.3 ','8','Green')
INSERT INTO @tbl([DATE], VALUE1, VALUE2, VALUE3, [TYPE]) VALUES('04/24/2014','10','1','11','Non-Green')
INSERT INTO @tbl([DATE], VALUE1, VALUE2, VALUE3, [TYPE]) VALUES('04/25/2014','10','2','10.8','Non-Green')
INSERT INTO @tbl([DATE], VALUE1, VALUE2, VALUE3, [TYPE]) VALUES('04/25/2014','1.4','5','12','Green')

--your required query
SELECT TOP 7 * FROM
(
    SELECT [date] AS d, 
    SUM(CASE WHEN [Type] = 'Green' AND Value1 >= 10 THEN 1 ELSE 0 END + CASE WHEN [Type] = 'Green' AND Value2 >= 10 THEN 1 ELSE 0 END + CASE WHEN [Type] = 'Green' AND Value3 >= 10 THEN 1 ELSE 0 END) AS Green,
    SUM(CASE WHEN [Type] = 'Non-Green' AND Value1 >= 10 THEN 1 ELSE 0 END + CASE WHEN [Type] = 'Non-Green' AND Value2 >= 10 THEN 1 ELSE 0 END + CASE WHEN [Type] = 'Non-Green' AND Value3 >= 10 THEN 1 ELSE 0 END) AS [Non-Green]   
    FROM @tbl 
    GROUP BY [date]
)x
ORDER BY d ASC

希望对你有帮助