透視表中的SQL

Question

加入我有表Tbl_Login

 
Cat_ID int 
Amount1 decimal 
Amount2 decimal 
Amount3 decimal 
dateon date 


Cat_ID Amount1 Amount2 Amount3 dateon 
1 10 12 12 2013-02-12 
2 10 12 12 2013-02-12 
3 10 12 12 2013-02-12 
4 10 12 12 2013-02-12 

1 20 22 22 2013-02-13 
2 20 22 22 2013-02-13 
3 20 22 22 2013-02-13 
5 20 22 22 2013-02-13 
I want To Mamber Enter Two Date 12/02/2013 15/02/2013 and 

colum1 Cat_ID 12-02-2013 13-02-2013 14-02-2013 15-02-2013 
Amount1 1  10  20  null  null  
Amount2 1  12  22  null  null 
Amount3 1  12  22  null  null  

Amount1 2  10  20  null  null  
Amount2 2  12  22  null  null 
Amount3 2  12  22  null  null  

Amount1 3  10  20  null  null  
Amount2 3  12  22  null  null 
Amount3 3  12  22  null  null  

Amount1 4  10  null null  null  
Amount2 4  12  null null  null 
Amount3 4  12  null null  null  

Amount1 5  null  20  null  null  
Amount2 5  null  22  null  null 
Amount3 5  null  22  null  null 

Answer 1

您沒有指定您所使用的RDBMS但有幾個方法，你可以將這些數據轉化爲你所需要的結果。

如果您使用的是不具有PIVOT功能的數據庫，那麼可以通過使用UNION ALL查詢unpivot的數據，然後使用聚合函數與CASE表達日期轉動到列中完成。查詢將類似於此：

select col, 
    cat_id, 
    max(case when dateon = '2013-02-12' then value end) [2013-02-12], 
    max(case when dateon = '2013-02-13' then value end) [2013-02-13], 
    max(case when dateon = '2013-02-14' then value end) [2013-02-14], 
    max(case when dateon = '2013-02-15' then value end) [2013-02-15] 
from 
(
    select cat_id, 'amount1' col, amount1 value, dateon 
    from tbl_login 
    where dateon >= '2013-02-12' 
    and dateon <= '2013-02-15' 
    union all 
    select cat_id, 'amount2' col, cast(amount2 as decimal(10,2)) value, dateon 
    from tbl_login 
    where dateon >= '2013-02-12' 
    and dateon <= '2013-02-15' 
    union all 
    select cat_id, 'amount3' col, cast(amount3 as decimal(10,2)) value, dateon 
    from tbl_login 
    where dateon >= '2013-02-12' 
    and dateon <= '2013-02-15' 
) src 
group by col, cat_id 
order by cat_id, col 

見SQL Fiddle with Demo

如果您正在使用SQL Server 2005+或Oracle 11g +，那麼你就可以同時使用UNPIVOT和PIVOT功能：

select col, cat_id, 
    [2013-02-12], [2013-02-13], 
    [2013-02-14], [2013-02-15] 
from 
(
    select cat_id, dateon, 
    col, value 
    from 
    (
    select cat_id, amount1, 
     cast(amount2 as decimal(10,2)) amount2, 
     cast(amount3 as decimal(10,2)) amount3, 
     dateon 
    from tbl_login 
    where dateon >= '2013-02-12' 
     and dateon <= '2013-02-15' 
) s 
    unpivot 
    (
    value 
    for col in (Amount1, Amount2, Amount3) 
) unpiv 
) src 
pivot 
(
    max(value) 
    for dateon in ([2013-02-12], [2013-02-13], 
       [2013-02-14], [2013-02-15]) 
) piv 
order by cat_id, col 

請參閱SQL Fiddle with Demo。

如果你有一個未知的數字，你要轉換爲列中的日期，那麼你可以使用動態SQL（注：動態代碼爲SQL Server的語法）：

DECLARE @cols AS NVARCHAR(MAX), 
    @query AS NVARCHAR(MAX), 
    @startdate datetime, 
    @enddate datetime 

set @startdate ='2013-02-12' 
set @enddate ='2013-02-15' 

;with dates (dt) as 
(
    select @startdate 
    union all 
    select dateadd(dd, 1, dt) 
    from dates 
    where dateadd(dd, 1, dt) <= @enddate 
) 
select dt 
into #temp 
from dates 

select @cols = STUFF((SELECT distinct ',' + QUOTENAME(convert(varchar(10), dt, 120)) 
        from #temp 
      FOR XML PATH(''), TYPE 
      ).value('.', 'NVARCHAR(MAX)') 
     ,1,1,'') 

set @query = 'SELECT col, cat_id,' + @cols + ' 
      from 
      (
       select cat_id, dateon, 
       col, value 
       from 
       (
       select cat_id, amount1, 
        cast(amount2 as decimal(10,2)) amount2, 
        cast(amount3 as decimal(10,2)) amount3, 
        dateon 
       from tbl_login 
       where dateon >= '''+convert(varchar(10), @startdate, 120)+''' 
        and dateon <= '''+convert(varchar(10), @enddate, 120)+''' 
      ) s 
       unpivot 
       (
       value 
       for col in (Amount1, Amount2, Amount3) 
      ) unpiv 
      ) src 
      pivot 
      (
       max(value) 
       for dateon in (' + @cols + ') 
      ) p 
      order by cat_id, col' 

execute(@query) 

見SQL Fiddle with Demo

所有查詢的結果是：

|  COL | CAT_ID | 2013-02-12 | 2013-02-13 | 2013-02-14 | 2013-02-15 | 
------------------------------------------------------------------------ 
| amount1 |  1 |   10 |   20 |  (null) |  (null) | 
| amount2 |  1 |   12 |   22 |  (null) |  (null) | 
| amount3 |  1 |   12 |   22 |  (null) |  (null) | 
| amount1 |  2 |   10 |   20 |  (null) |  (null) | 
| amount2 |  2 |   12 |   22 |  (null) |  (null) | 
| amount3 |  2 |   12 |   22 |  (null) |  (null) | 
| amount1 |  3 |   10 |   20 |  (null) |  (null) | 
| amount2 |  3 |   12 |   22 |  (null) |  (null) | 
| amount3 |  3 |   12 |   22 |  (null) |  (null) | 
| amount1 |  4 |   10 |  (null) |  (null) |  (null) | 
| amount2 |  4 |   12 |  (null) |  (null) |  (null) | 
| amount3 |  4 |   12 |  (null) |  (null) |  (null) | 
| amount1 |  5 |  (null) |   20 |  (null) |  (null) | 
| amount2 |  5 |  (null) |   22 |  (null) |  (null) | 
| amount3 |  5 |  (null) |   22 |  (null) |  (null) |