SQL Server 2005/2008 Group By statement with parameters without using dynamic SQL?

Question

Is there a way to write SQL Server Stored Procedure which to be strongly typed ( i.e. returning known result set of columns ) and having its group statement to be dynamic. <

Answer 1

You can group on a constant which might be useful

SELECT
    SUM(Column0),
    CASE @MyVar WHEN 'Column1' THEN Column1 ELSE '' END AS MyGrouping
FROM
    Table1
GROUP BY
    CASE @MyVar WHEN 'Column1' THEN Column1 ELSE '' END

Edit: For datatype mismatch and multiple values and this allows you to group on both columns...

SELECT
    SUM(Column0),
    CASE @MyVar WHEN 'Column1' THEN Column1 ELSE NULL END AS Column1,
    CASE @MyVar WHEN 'Column2' THEN Column2 ELSE NULL END AS Column2
FROM
    Table1
GROUP BY
    CASE @MyVar WHEN 'Column1' THEN Column1 ELSE NULL END,
    CASE @MyVar WHEN 'Column2' THEN Column2 ELSE NULL END

Answer 2

You are about to shoot yourself in the foot and are asking for a bigger bullet.

The only sensible approach to this is to separate the IF into a T-SQL flow control statement:

IF (0 = @MyVar)
 SELECT SUM(Column0) FROM Table1 GROUP BY Column1;
ELSE IF (1 = @MyVar)
  SELECT SUM(Column0) FROM Table1 GROUP BY Column2;
ESLE IF (2 = @myVar)
  SELECT SUM(Column0) FROM Table1 GROUP BY Column3;

The last thing you want from the query optimizer is to generate a plan that has to GROUP BY a condition that is determined by a variable.