Pivot (Dynamic)

USE [master]
GO

/****** Object: StoredProcedure [dbo].[sp_pivot] Script Date: 07/07/2010 14:26:48 ******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE PROC [dbo].[sp_pivot]
@query AS NVARCHAR(MAX),
@on_rows AS NVARCHAR(MAX),
@on_cols AS NVARCHAR(MAX),
@agg_func AS NVARCHAR(MAX) = N'MAX',
@agg_col AS NVARCHAR(MAX)

AS
DECLARE
@sql AS NVARCHAR(MAX),
@cols AS NVARCHAR(MAX),
@newline AS NVARCHAR(2);
SET @newline = NCHAR(13) + NCHAR(10);
-- If input is a valid table or view
-- construct a SELECT statement against it
IF COALESCE(OBJECT_ID(@query, N'U'),
OBJECT_ID(@query, N'V')) IS NOT NULL
SET @query = N'SELECT * FROM ' + @query;
-- Make the query a derived table
SET @query = N'(' + @query + @newline + N' ) AS Query';
-- Handle * input in @agg_col
IF @agg_col = N'*'
SET @agg_col = N'1';
-- Construct column list
SET @sql =
N'SET @result = ' + @newline +
N' STUFF(' + @newline +
N' (SELECT N'','' + '
+ N'QUOTENAME(pivot_col) AS [text()]' + @newline +
N' FROM (SELECT DISTINCT('
+ @on_cols + N') AS pivot_col' + @newline +
N' FROM' + @query + N') AS DistinctCols' + @newline +
N' ORDER BY pivot_col' + @newline +
N' FOR XML PATH('''')),' + @newline +
N' 1, 1, N'''');'
EXEC sp_executesql
@stmt = @sql,
@params = N'@result AS NVARCHAR(MAX) OUTPUT',
@result = @cols OUTPUT;
-- Create the PIVOT query
SET @sql =
N'SELECT *' + @newline +
N'FROM' + @newline +
N' ( SELECT ' + @newline +
N' ' + @on_rows + N',' + @newline +
N' ' + @on_cols + N' AS pivot_col,' + @newline +
N' ' + @agg_col + N' AS agg_col' + @newline +
N' FROM ' + @newline +
N' ' + @query + @newline +
N' ) AS PivotInput' + @newline +
N' PIVOT' + @newline +
N' ( ' + @agg_func + N'(agg_col)' + @newline +
N' FOR pivot_col' + @newline +
N' IN(' + @cols + N')' + @newline +
N' ) AS PivotOutput;'
EXEC sp_executesql @sql;
GO