How to trace T-SQL function calls

Question

I\'m trying to debug a rather complicated formula evaluator written in T-SQL UDFs (don\'t ask) that recursively (but indirectly through an intermediate func

Answer 1

Why not use SQL Profiler with statement level events added?

Edit: Add events for Stored Procedures : SP:Stmt Starting or SP:Stmt Completed Use variables to debug if needed, i.e. set @debug='i am here'; UDF's, while not technically stored procedures, will get traced with the statement level events.

Answer 2

Can you take your function, and make a second copy of it, but returning a table type with an additional column for your debug information.

For example, the mySum function below

CREATE FUNCTION mySum
(   
    @param1 int,
    @param2 int
)
RETURNS INT AS
BEGIN
    DECLARE @mySum int

    SET @mySum = @param1

    SET @mySum = @mySum + @param2

    RETURN @mySum

END
GO
SELECT dbo.mySum(1, 2)

Would turn into

CREATE FUNCTION mySumDebug
(   
    @param1 int,
    @param2 int
)
RETURNS @myTable TABLE
(
    [mySum] int,
    [debug] nvarchar(max)
)
AS
BEGIN
    DECLARE @debug nvarchar(max)

    SET @debug = 'Declare @mySum variable. '
    DECLARE @mySum int

    SET @debug = @debug + 'Set @mySum = @param1(' + CONVERT(nvarchar(50), @param1) + ') '
    SET @mySum = @param1


    SET @debug = @debug + 'Add @param2(' + CONVERT(nvarchar(50), @param2) + ') to @mySum(' + CONVERT(nvarchar(50), @mySum) + ') '
    SET @mySum = @mySum + @param2

    SET @debug = @debug + 'Return @mySum variable. '

    INSERT @myTable (mySum, debug) VALUES (@mySum, @debug)

    RETURN
END
GO
SELECT mySum, debug FROM dbo.mySumDebug(1, 2)

Not an ideal solution, but useful just to return some text to help track down a bug.

Answer 3

This looks like what you need but it's only available in team/pro versions of Visual Studio.