需要枢轴帮助

Question

我有一张这样的桌子.表格1.

Customer    Product     Value   Quantity    Order Number


Dave    Product 1   15  1   154
Dave    Product 2   25  5   154
Dave    Product 3   45  4   15
Rob     Product 2   222 33  233

现在我想要这个,表2.

Customer    Product 1 Quantity  Product 1 Value     Price per item ( Value /Quantity) for Product 1     Product 2 Quantity  Product 2 Value     Price per item ( Value /Quantity) for Product 2     Product 3 Quantity  Product 3 Value     Price per item ( Value /Quantity) for Product 3 Order Number 

Dave    1   15  15  5   25  5   null    null    null    154

Dave    null    null    null    null    null    Null    4   45  11.25   15

Rob     null    null    null    33  222 6.727272727 null    null    null    233

我在考虑一些支点但不确定如何构建它.产品数量也没有固定,见表1.

Answer 1

为了得到结果,我建议同时对数据应用unpivot和pivot.

UNPIVOT会将表中的列数据转换为行.数据未分配后,您可以应用数据透视表.

由于您使用的是SQL Server 2008+,因此可以使用带有VALUES子句的CROSS APPLY进行取消转换.在2008年之前,您可以使用UNPIVOT功能.取消数据的代码是:

select t.customer,
  replace(t.product, ' ', '')+'_'+c.col piv_col, 
  c.val,
  t.ordernumber
from table1 t
cross apply
(
  values
    ('value', cast(value as varchar(10))),
    ('quantity', cast(quantity as varchar(10))),
    ('PricePerUnit', cast((value/quantity) *1.0 as varchar(10)))
) c (col, val);

见演示.这会将数据转换为以下格式:

| CUSTOMER |               PIV_COL |  VAL | ORDERNUMBER |
---------------------------------------------------------
|     Dave |        Product1_value |   15 |         154 |
|     Dave |     Product1_quantity |    1 |         154 |
|     Dave | Product1_PricePerUnit | 15.0 |         154 |
|     Dave |        Product2_value |   25 |         154 |

您可以看到Dave订单154 的行已经变成了行,我创建了将用于pivot(piv_col)的新列名.此列已将产品名称连接到前一列标题(值,数量)的起始位置.

由于数据在一行中,因此您可以轻松地将数据透视功能应用于数据.最终的代码是:

select customer,
  Product1_quantity, Product1_value, Product1_PricePerUnit,
  Product2_quantity, Product2_value, Product2_PricePerUnit,
  Product3_quantity, Product3_value, Product3_PricePerUnit,
  orderNumber
from
(
  select t.customer,
    replace(t.product, ' ', '')+'_'+c.col piv_col, 
    c.val,
    t.ordernumber
  from table1 t
  cross apply
  (
    values
      ('value', cast(value as varchar(10))),
      ('quantity', cast(quantity as varchar(10))),
      ('PricePerUnit', cast((value/quantity) *1.0 as varchar(10)))
  ) c (col, val)
) d
pivot
(
  max(val)
  for piv_col in(Product1_quantity, Product1_value, Product1_PricePerUnit,
                 Product2_quantity, Product2_value, Product2_PricePerUnit,
                 Product3_quantity, Product3_value, Product3_PricePerUnit)
) piv;

请参阅SQL Fiddle with Demo.

如果你有一个已知数量的产品,上面的工作很好,但如果没有,那么你将需要使用动态SQL.

DECLARE @cols AS NVARCHAR(MAX),
    @query  AS NVARCHAR(MAX)

select @cols = STUFF((SELECT  ',' + QUOTENAME(replace(t.product, ' ', '')+'_'+c.col) 
                    from Table1 t
                    cross apply
                    (
                      values ('value', 1), ('quantity', 0),('PricePerUnit', 3)
                    ) c (col, so)    
                    group by product, col, so
                    order by product, so
            FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)') 
        ,1,1,'')

set @query = 'SELECT customer, ' + @cols + ', ordernumber
              from
              (
                select t.customer,
                  replace(t.product, '' '', '''')+''_''+c.col piv_col, 
                  c.val,
                  t.ordernumber
                from table1 t
                cross apply
                (
                  values
                    (''value'', cast(value as varchar(10))),
                    (''quantity'', cast(quantity as varchar(10))),
                    (''PricePerUnit'', cast((value/quantity) *1.0 as varchar(10)))
                ) c (col, val)
              ) d
              pivot
              (
                max(val)
                for piv_col in (' + @cols + ')
              ) p '

execute(@query);

请参阅SQL Fiddle with Demo.这些查询给出了结果:

| CUSTOMER | PRODUCT1_QUANTITY | PRODUCT1_VALUE | PRODUCT1_PRICEPERUNIT | PRODUCT2_QUANTITY | PRODUCT2_VALUE | PRODUCT2_PRICEPERUNIT | PRODUCT3_QUANTITY | PRODUCT3_VALUE | PRODUCT3_PRICEPERUNIT | ORDERNUMBER |
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|     Dave |            (null) |         (null) |                (null) |            (null) |         (null) |                (null) |                 4 |             45 |                  11.0 |          15 |
|     Dave |                 1 |             15 |                  15.0 |                 5 |             25 |                   5.0 |            (null) |         (null) |                (null) |         154 |
|      Rob |            (null) |         (null) |                (null) |                33 |            222 |                   6.0 |            (null) |         (null) |                (null) |         233 |