Ran trong vấn đề này ngày hôm nay, và đã đăng trên blog của tôi. Mô tả ngắn gọn về giải pháp là tạo một bảng tạm thời với một cột và sau đó ALTER nó động bằng cách sử dụng sp_executesql. Sau đó, bạn có thể chèn kết quả của PIVOT động vào đó. Ví dụ làm việc bên dưới.
CREATE TABLE #Manufacturers
(
ManufacturerID INT PRIMARY KEY,
Name VARCHAR(128)
)
INSERT INTO #Manufacturers (ManufacturerID, Name)
VALUES (1,'Dell')
INSERT INTO #Manufacturers (ManufacturerID, Name)
VALUES (2,'Lenovo')
INSERT INTO #Manufacturers (ManufacturerID, Name)
VALUES (3,'HP')
CREATE TABLE #Years
(YearID INT, Description VARCHAR(128))
GO
INSERT INTO #Years (YearID, Description) VALUES (1, '2014')
INSERT INTO #Years (YearID, Description) VALUES (2, '2015')
GO
CREATE TABLE #Sales
(ManufacturerID INT, YearID INT,Revenue MONEY)
GO
INSERT INTO #Sales (ManufacturerID, YearID, Revenue) VALUES(1,2,59000000000)
INSERT INTO #Sales (ManufacturerID, YearID, Revenue) VALUES(2,2,46000000000)
INSERT INTO #Sales (ManufacturerID, YearID, Revenue) VALUES(3,2,111500000000)
INSERT INTO #Sales (ManufacturerID, YearID, Revenue) VALUES(1,1,55000000000)
INSERT INTO #Sales (ManufacturerID, YearID, Revenue) VALUES(2,1,42000000000)
INSERT INTO #Sales (ManufacturerID, YearID, Revenue) VALUES(3,1,101500000000)
GO
DECLARE @SQL AS NVARCHAR(MAX)
DECLARE @PivotColumnName AS NVARCHAR(MAX)
DECLARE @TempTableColumnName AS NVARCHAR(MAX)
DECLARE @AlterTempTable AS NVARCHAR(MAX)
--get delimited column names for various SQL statements below
SELECT
-- column names for pivot
@PivotColumnName= ISNULL(@PivotColumnName + N',',N'') + QUOTENAME(CONVERT(NVARCHAR(10),YearID)),
-- column names for insert into temp table
@TempTableColumnName = ISNULL(@TempTableColumnName + N',',N'') + QUOTENAME('Y' + CONVERT(NVARCHAR(10),YearID)),
-- column names for alteration of temp table
@AlterTempTable = ISNULL(@AlterTempTable + N',',N'') + QUOTENAME('Y' + CONVERT(NVARCHAR(10),YearID)) + ' MONEY'
FROM (SELECT DISTINCT [YearID] FROM #Sales) AS Sales
CREATE TABLE #Pivot
(
ManufacturerID INT
)
-- Thats it! Because the following step will flesh it out.
SET @SQL = 'ALTER TABLE #Pivot ADD ' + @AlterTempTable
EXEC sp_executesql @SQL
--execute the dynamic PIVOT query into the temp table
SET @SQL = N'
INSERT INTO #Pivot (ManufacturerID, ' + @TempTableColumnName + ')
SELECT ManufacturerID, ' + @PivotColumnName + '
FROM #Sales S
PIVOT(SUM(Revenue)
FOR S.YearID IN (' + @PivotColumnName + ')) AS PivotTable'
EXEC sp_executesql @SQL
SELECT M.Name, P.*
FROM #Manufacturers M
INNER JOIN #Pivot P ON M.ManufacturerID = P.ManufacturerID