Execute the following T-SQL script in Query Editor to create and apply an subtraction drills stored procedure:

USE AdventureWorks

GO

-- SQL Server stored procedure with parameters

-- SQL random number

CREATE PROC sprocMathTrainerSubtraction(

           @DrillNumber INT,

           @Level       INT,

           @Result      BIT)

AS

  BEGIN

    DECLARE  @Counter SMALLINT

    DECLARE  @Drill  TABLE(

                           SEQUENCE INT,

                           [Left]   INT,

                           [Right]  INT,

                           Result   VARCHAR(15)

                           )

    SET @Counter = 1

    WHILE @Counter <= @DrillNumber

      BEGIN

        INSERT @Drill

        SELECT @Counter,

               @Level * RAND(),

               @Level * RAND(),

               ''

        DELETE @Drill

        WHERE  [Left] < [Right]

        IF @@ROWCOUNT > 0

          CONTINUE

        SET @Counter = @Counter + 1

      END

    SELECT convert(VARCHAR,SEQUENCE) + '. ' + convert(VARCHAR,[Left]) +

' - ' + convert(VARCHAR,[Right]) + ' = '

    FROM   @Drill

    IF @Result = 1

      BEGIN

        UPDATE @Drill

        SET    Result = convert(VARCHAR,([Left] - [Right]))

        SELECT convert(VARCHAR,SEQUENCE) + '. ' + convert(VARCHAR,[Left]) +

' - ' + convert(VARCHAR,[Right]) + ' = ' + Result

        FROM   @Drill

      END

  END

GO

EXEC sprocMathTrainerSubtraction

  60 ,

  30 ,

  1

GO

/* Partial results

1. 22 - 1 =

2. 25 - 3 =

3. 12 - 12 =

4. 19 - 4 =

5. 28 - 28 =

6. 26 - 15 =

7. 24 - 10 =

8. 8 - 7 =

*/