带有聚合和总计的 SQL Pivot 查询

如何解决带有聚合和总计的 SQL Pivot 查询

表-A

ProductId	品牌
1	品牌 1
2	品牌 2
3	品牌 3

表-B

DCDate	DCNo	ProductId	重量
2021-03-09	3	1	12.5
2021-03-09	3	1	12.6
2021-03-09	3	1	12.5
2021-03-09	3	2	10.5
2021-03-09	3	2	10.4
2021-03-09	3	3	15.5
2021-03-09	1	1	12.5
2021-03-09	1	3	15.7
2021-03-09	2	2	10.6
2021-03-09	4	1	12.7
2021-03-09	4	1	12.6

预期结果：-

品牌	1	2	3	4
品牌 1	1	0	3	2
品牌 2	0	1	2	0
品牌 3	1	0	1	0

需要动态数据透视查询

我尝试了什么

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

select @cols = STUFF((SELECT ',' + QUOTENAME([DCNo]) from [Table-B] FOR XML PATH(''),TYPE).value('.','NVARCHAR(MAX)'),1,'')

set @query = 'SELECT ' + @cols + '
             from 
             (
                SELECT a.[DCNo],b.[BrandName],count(*) as Total FROM [Table-B] a inner join [Table-A] b on a.[ProductID]=b.[ProductID] group by [DCNo],b.[BrandName] order by DCNo,b.[BrandName]
            ) x
            pivot 
            (
                max(Total)
                for DCNo in (' + @cols + ')
            ) p '

execute(@query)

解决方法

我在 sqlfiddle 中重新创建了它： http://sqlfiddle.com/#!18/d1554/9 。 你很接近，但我有时发现将所有总和/计数/分组逻辑移到查询的 PIVOT 部分更容易。结果是更简单的查询（大多数情况下）

CREATE TABLE [Table-A] (
  ProductId INT,BrandName VARCHAR(50)
)

CREATE TABLE [Table-B](
  DCDate DATETIME,DCNo INT,ProductId INT,Weight DECIMAL
)

INSERT INTO [Table-A] VALUES
(1,'CAT'),(2,'APPLE'),(3,'PARROT')

INSERT INTO [Table-B] VALUES
('2021-03-09',3,1,12.5),('2021-03-09',12.6),2,10.5),10.4),15.5),15.7),10.6),4,12.7),12.6)

-- Query
DECLARE @cols AS NVARCHAR(MAX) = '';
DECLARE @nullcols AS NVARCHAR(MAX) = '';
DECLARE @query  AS NVARCHAR(MAX);

-- Determine columns
;WITH cte AS (
  SELECT 
    DISTINCT 
    dcno,',' + QUOTENAME([DCNo]) AS col,ISNULL(' + QUOTENAME([DCNo]) + ',0) AS ' + QUOTENAME([DCNo]) AS nullcol
  FROM [Table-B]
)
SELECT
  @cols += col,@nullcols += nullcol
FROM cte
ORDER BY dcno
SET @cols = SUBSTRING(@cols,LEN(@cols)) 

-- create query
SET @query = N';with CTE AS 
(
  SELECT 
    a.BrandName,a.ProductId,b.DCNo,1 as Value
  FROM [Table-A] a
  INNER JOIN [Table-B] b
     ON a.ProductId = b.ProductId
)
SELECT BrandName ' + @nullcols + ' FROM 
(SELECT * FROM cte) p
PIVOT
(
  SUM(Value)
  FOR DCNo IN (' + @cols + ')    
) AS pvt
ORDER BY pvt.ProductId
'
-- SELECT @query
execute(@query)