Question

I am really struggling with figuring out how to convert a MS Access CrossTab query into T-SQL to run on SQL2000 or into Linq-to-SQL. What I have is a query that looks like this in Access:

And produces this:

The query basically groups by ItemID and StoreID and Sums the Qty sold, but with the CrossTab query in Access, I am able to have a unique ItemID for each row, a column for each StoreID, and the total Qty for each StoreID/ItemID combination as the value.

How do you construct this in T-SQL 2000? I can build a simple select query with grouping, but it gives me the data in three columns, StoreID, ItemID, and Qty. But what I need is a column for ItemID and a column for every StoreID in the result set

SELECT     Trans.TranSID as StoreID, TransDetail.TranItemID as ItemID, SUM(TransDetail.Qty) AS TotalQtyForStore
    FROM         Trans INNER JOIN
                          TransDetail ON Trans.TranID = TransDetail.TranID INNER JOIN
                          Item ON TransDetail.TranItemID = Item.ItemID
    WHERE     (Trans.TranDate > CONVERT(DATETIME, '2005-01-01 00:00:00', 102)) AND (Trans.TranTypeID = 'so' OR
                          Trans.TranTypeID = 'ca') AND (Trans.TranStatus <> 'v') AND (Item.ItemClassID = 'RHM')
    GROUP BY Trans.TranSID, TransDetail.TranItemID

Which produces this:

But what I really need to do is transform this data so that the StoreID values become columns, like the Access CrossTab query above.

Answer 1

I would do this with dynamic SQL, since you probably don’t know all of the store (TranSID) values in advance. This stored procedure takes start/end date as parameters, and generates a cross-tab. You can probably parameterize some of the other things as well, such as TranStatus and ItemClassID, but it wasn’t clear if those are fixed or variable elements in your query.

CREATE PROCEDURE dbo.CrossTabByItem
  @StartDate DATETIME,
  @EndDate   DATETIME = NULL
AS
BEGIN
  SET NOCOUNT ON;

  SET @EndDate = COALESCE(DATEADD(DAY, 1, @EndDate), GETDATE());

  DECLARE @sql NVARCHAR(4000); SET @sql = N'';

  SELECT @sql = @sql + ',
    [' + TranSID + '] = SUM(CASE WHEN t.TranSID = ''' 
    + TranSID + ''' THEN td.Qty ELSE 0 END)' FROM 
    (
      SELECT DISTINCT TranSID FROM dbo.Trans
      WHERE TranDate >= @StartDate AND TranDate < @EndDate
    ) AS x ORDER BY TranSID;

    SET @sql = N'SELECT ItemID = td.TranItemID' + @sql + '
      FROM dbo.Trans AS t
      INNER JOIN dbo.TransDetail AS td
       ON t.TranID = td.TranID
      INNER JOIN dbo.Item AS i
       ON td.TranItemID = i.ItemID
      WHERE t.TranDate >= @StartDate
      AND t.TranDate < @EndDate
      AND t.TranTypeID IN (''so'',''ca'')
      AND t.TranStatus <> ''v''
      AND i.ItemClassID = ''RHM''
      GROUP BY td.TranItemID;';

    EXEC sp_executesql @sql, 
      N'@StartDate DATETIME, @EndDate DATETIME', 
      @StartDate, @EndDate;
END
GO

So you can call it like this, to get everything from January 1st, 2005 until right now:

EXEC dbo.CrossTabByItem @StartDate = '20050101';

Or like this, to get just January of 2005:

EXEC dbo.CrossTabByItem @StartDate = '20050101', @EndDate = '20050131';