SQL Server－动态Pivot表的存储过程

/****** Object: StoredProcedure [dbo].[pivotsp] Script Date: 01/11/2013 14:08:29 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
ALTER PROC [dbo].[pivotsp]
@query AS NVARCHAR(MAX), -- The query, can also be the name of a table/view.
@on_rows AS NVARCHAR(MAX), -- The columns that will be regular rows.
@on_cols AS NVARCHAR(MAX), -- The columns that are to be pivoted.
@agg_func AS NVARCHAR(257) = N'SUM', -- Aggregate function.
@agg_col AS NVARCHAR(MAX), -- Column to aggregate.
@output AS NVARCHAR(257) = N'', -- Table for results
@debug AS bit = 0 -- 1 for debugging
AS

-- Example usage:
-- exec pivotsp
-- 'select * from vsaleshistory',
-- 'market,marketid,family,familyid,Forecaster,Forecasterid,product,productid',
-- 'month',
-- 'sum',
-- 'ku',
-- '##sales'

-- Input validation
IF @query IS NULL OR @on_rows IS NULL OR @on_cols IS NULL
OR @agg_func IS NULL OR @agg_col IS NULL
BEGIN
RAISERROR('Invalid input parameters.', 16, 1);
RETURN;
END

-- Additional input validation goes here (SQL Injection attempts, etc.)

BEGIN TRY
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 + 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'','' + quotename( '
+ 'CAST(pivot_col AS sysname)' +
+ ') 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'''');'

IF @debug = 1
PRINT @sql

EXEC sp_executesql
@stmt = @sql,
@params = N'@result AS NVARCHAR(MAX) OUTPUT',
@result = @cols OUTPUT;

IF @debug = 1
PRINT @cols

-- Create the PIVOT query
IF @output = N''
begin
SET @sql =
N'SELECT *' + @newline +
N'FROM (SELECT '
+ @on_rows
+ N', ' + @on_cols + N' AS pivot_col'
+ N', ' + @agg_col + N' AS agg_col' + @newline +
N' FROM ' + @query + N')' +
+ N' AS PivotInput' + @newline +
N' PIVOT(' + @agg_func + N'(agg_col)' + @newline +
N' FOR pivot_col IN(' + @cols + N')) AS PivotOutput;'
end
ELSE
begin
set @sql = 'IF EXISTS (SELECT * FROM tempdb.sys.objects WHERE ' +
'name = ''' + @output + ''' AND type = N''U'') DROP TABLE tempdb.' + @output
EXEC sp_executesql @sql;

SET @sql =
N'SELECT * INTO ' + @output + @newline +
N'FROM (SELECT '
+ @on_rows
+ N', ' + @on_cols + N' AS pivot_col'
+ N', ' + @agg_col + N' AS agg_col' + @newline +
N' FROM ' + @query + N')' +
+ N' AS PivotInput' + @newline +
N' PIVOT(' + @agg_func + N'(agg_col)' + @newline +
N' FOR pivot_col IN(' + @cols + N')) AS PivotOutput;'
end

IF @debug = 1
PRINT @sql

EXEC sp_executesql @sql;
END TRY
BEGIN CATCH
DECLARE
@error_message AS NVARCHAR(2047),
@error_severity AS INT,
@error_state AS INT;

SET @error_message = ERROR_MESSAGE();
SET @error_severity = ERROR_SEVERITY();
SET @error_state = ERROR_STATE();

RAISERROR(@error_message, @error_severity, @error_state);

RETURN;
END CATCH