sql - 对不同记录进行 PIVOT 查询

Question

我有下表:

------------------------------------------------------
| Id    Code  percentage  name  name1   activity     |
-----------------------------------------------------
| 1   Prashant  43.43    James  James_  Running      |
| 1   Prashant  70.43    Sam    Sam_    Cooking      |
| 1   Prashant  90.34    Lisa   Lisa_   Walking      |
| 1   Prashant  0.00     James  James_  Stealing     |
| 1   Prashant  0.00     James  James_  Lacking      |
| 1   Prashant  73       Sam     Sam_   Cooking 1    |
------------------------------------------------------

问题是，由于 MAX 函数，它忽略了列名 Name1 为 Lacking 的 0.00 值

预期结果:

-------------------------------------------------------------------
Id  Code        James    James_  Sam        Sam_    Lisa      Lisa_
-------------------------------------------------------------------
1   Prashant    Running  43.43  Cooking     3.43    Walking   90.34
1   Prashant    Stealing 0.0    Cooking 1   73      NULL      NULL
1   Prashant    Lacking  0.0    NULL        NULL    NULL      NULL
-------------------------------------------------------------------

PIVOT 查询我尝试过的内容:

DECLARE @DynamicPivotQuery NVARCHAR(MAX)

SET @DynamicPivotQuery  = N'SELECT Id,Code,James,James_,Sam,Sam_,Lisa,Lisa_
    INTO ##TempPivot 
    FROM A
    PIVOT(MAX(activity)
          FOR name IN (James,Sam,Lisa)) AS PVTTable PIVOT
          (
          MAX(percentage)
          FOR name1 IN (James_,Sam_,Lisa_)) AS PVTTable1'


EXECUTE(@DynamicPivotQuery) 

SELECT * 
INTO #RESULT 
FROM ##TempPivot


SELECT * 
FROM #RESULT

生成数据的示例查询:

CREATE TABLE A
(
  Id NVARCHAR(10),
  Code NVARCHAR(MAX),
  percentage NVARCHAR(MAX),
  name NVARCHAR(MAX),
  name1 NVARCHAR(MAX),
  activity NVARCHAR(MAX)
)


INSERT INTO A VALUES (1,'Prashant',43.43,'James','James_','Running')
INSERT INTO A VALUES (1,'Prashant',3.43,'Sam','Sam_','Cooking')
INSERT INTO A VALUES (1,'Prashant',90.34,'Lisa','Lisa_','Walking')
INSERT INTO A VALUES (1,'Prashant',0.00,'James','James_','Stealing')
INSERT INTO A VALUES (1,'Prashant',0.00,'James','James_','Lacking')
INSERT INTO A VALUES (1,'Prashant',73,'Sam','Sam_','Cooking 1')

Answer 1

如果您将 ROW_NUMBER() 添加到组合中，您的数据透视表将能够保留事件和百分比之间的关联。

;with cte as 
(
    select *, ROW_NUMBER() over (partition by name order by percentage desc) ROWNUM
    from A
),
cte2 as
(
    SELECT Id,Code,ROWNUM,James,James_,Sam,Sam_,Lisa,Lisa_
    FROM cte
    PIVOT(MAX(activity)
          FOR name IN (James,Sam,Lisa)) AS PVTTable PIVOT
          (
          MAX(percentage)
          FOR name1 IN (James_,Sam_,Lisa_)) AS PVTTable1
)
select Id, Code, MAX(James) James, MAX(James_) James_, MAX(Sam) Sam, MAX(Sam_) Sam_, MAX(Lisa) Lisa, MAX(Lisa_) Lisa_
from cte2
group by Id, Code, ROWNUM

返回:

Id  Code        James       James_  Sam         Sam_    Lisa    Lisa_
1   Prashant    Running     43.43   Cooking 1   73      Walking 90.34
1   Prashant    Stealing    0.00    Cooking     3.43    NULL    NULL
1   Prashant    Lacking     0.00    NULL        NULL    NULL    NULL

这个想法是，在第一个公共(public)表表达式中，将 A 表转换为:

Id  Code        percentage  name    name1   activity    ROWNUM
1   Prashant    43.43       James   James_  Running     1
1   Prashant    0.00        James   James_  Stealing    2
1   Prashant    0.00        James   James_  Lacking     3
1   Prashant    90.34       Lisa    Lisa_   Walking     1
1   Prashant    73          Sam     Sam_    Cooking 1   1
1   Prashant    3.43        Sam     Sam_    Cooking     2

在剩下的查询中，ROWNUM 列仅用于将百分比值绑定(bind)到事件。

一旦您有了有效的查询，使其动态化就很容易了。只需将所有动态部分(在本例中为逗号分隔的名称列表，对吧？)替换为变量即可。像这样的事情:

declare @sql nvarchar(max)
declare @name_concat nvarchar(max)
declare @name1_concat nvarchar(max)
declare @select_aggs nvarchar(max)
select @name_concat = STUFF((select distinct ',' + quotename(name) from A order by 1 for xml path('')), 1, 1, '')
select @name1_concat = STUFF((select distinct ',' + quotename(name1) from A order by 1 for xml path('')), 1, 1, '')

;with cte_all_names as (
    select name from A
    union all 
    select name1 from A
)
select @select_aggs = STUFF((select distinct ',MAX(' + quotename(name) + ') ' + quotename(name) from cte_all_names order by 1 for xml path('')), 1, 1, '')

select @sql = '
;with cte as 
(
    select *, ROW_NUMBER() over (partition by name order by percentage desc) ROWNUM
    from A
),
cte2 as
(
    SELECT Id,Code,ROWNUM,' + @name_concat + ',' + @name1_concat + '
    FROM cte
    PIVOT(MAX(activity)
          FOR name IN (' + @name_concat + ')) AS PVTTable PIVOT
          (
          MAX(percentage)
          FOR name1 IN (' + @name1_concat + ')) AS PVTTable1
)
select Id, Code, ' + @select_aggs + '
from cte2
group by Id, Code, ROWNUM
'

exec sp_executesql @sql