CREATE PROCEDURE dbo.[Forum_Bookmark_Threads_CreateDelete]
    (
      @ThreadID INT,
      @UserID INT,
      @Add BIT,
      @ModuleID INT
    )
AS
    IF @Add = 1
        BEGIN
            IF NOT EXISTS ( SELECT  [UserID]
                            FROM    dbo.Forum_Bookmark_Threads
                            WHERE   [ThreadID] = @ThreadID
                                    AND [UserID] = @UserID )
                BEGIN
                    INSERT  INTO dbo.Forum_Bookmark_Threads
                            (
                              [ThreadID],
                              [UserID],
                              [ModuleID]
                      )
                    VALUES  (
                              @ThreadID,
                              @UserID,
                              @ModuleID
                      )
                END
        END
    IF @Add = 0
        BEGIN
            DELETE  FROM dbo.Forum_Bookmark_Threads
            WHERE   [ThreadID] = @ThreadID
                    AND [UserID] = @UserID
        END

GO