Question : convert adjacency model table into nested set model table

OK, after reading tons of info on nested sets (really, I have read every article on the web concerning nested sets) I have squared my process into the following bit of SQL that will convert my adjacency table into a nested sets table:

TABLE: "tbl_Personnel_Supervisors"
Supervision_ID (PK)
User_ID
Supervisor_ID
Lft
rgt

Based on this table the following SQL will poulate the lft/rgt values in my table to properly convert it for nestedset type queries. HOWEVER, when I deploy, I will not be able to deploy to MS SQL Server... INSTEAD, I have to deploy to MS Access(Dont GASP, yes thats right downsize). SO, how can I convert the following into something I can use with Access?

For some more input, I am only using Access as the back-end, the UI will be all ASP/VBScript on the Web, the company just hasnt forked up the money for SQL Server yet:

-- Create the stack table
DECLARE @tmpStack TABLE
  (
    Supervision_ID INT IDENTITY(1, 1),
    User_ID INT NOT NULL,
    Lft INT NULL,
    rgt INT NULL
  )

-- what we do is start from a parent, in this instance
-- we want to start from the very top which is the NULL parent
DECLARE @Supervisor_ID AS INTEGER
SET @Supervisor_ID = NULL

-- our counter is the variable used to set the left and right extent
DECLARE @counter AS INTEGER
SET @counter = 1

-- what we do is go check the parentid for children, if it
-- has children we push
-- it into the stack and move on to the next child
DECLARE @Supervision_ID AS INTEGER
DECLARE @oldid AS INTEGER

SET NOCOUNT ON

WHILE 1 = 1
BEGIN
SET @Supervision_ID = NULL

  -- get the first row which is a child of @partentid, which has not already
  -- been pushed onto the stack
  INSERT INTO @tmpStack
    (
      User_ID,
      Lft
    )
  SELECT TOP 1 User_ID, @counter
  FROM tbl_Personnel_Supervisors
  WHERE ISNULL(Supervisor_ID, 0) = ISNULL(@Supervisor_ID,0)
  AND User_ID NOT IN (SELECT User_ID FROM @tmpStack)



  -- just check we are getting the right identity value
  -- this value does not get reset once its reas so we
  -- need to see if its the same as the older one
  SET @Supervision_ID = SCOPE_IDENTITY()
  IF ISNULL(@Supervision_ID, 0) = ISNULL(@oldid, 0)
    SET @Supervision_ID = NULL
    ELSE
  BEGIN
    SET @oldid = @Supervision_ID
    SET @counter = @counter + 1
  END


  -- if we have children (i.e if this operation inserted a row,
  -- then we carry on
  IF @Supervision_ID IS NULL
  BEGIN
    -- no rows left, which means we want to pop the last item
    SELECT TOP 1 @Supervision_ID = Supervision_ID FROM @tmpStack
    WHERE rgt IS NULL ORDER BY Supervision_ID DESC
   
    -- there are no items left to pop, so exit the procedure
    IF @Supervision_ID IS NULL
      BREAK

    UPDATE @tmpStack
    SET rgt = @counter
    WHERE Supervision_ID = @Supervision_ID

    SET @counter = @counter + 1

    SELECT @Supervisor_ID = Supervisor_ID
    FROM tbl_Personnel_Supervisors WHERE User_ID =
      (SELECT User_ID FROM @tmpStack WHERE Supervision_ID = @Supervision_ID)
  END
  ELSE
  BEGIN
    -- this is easy enough, move on to the next level
    -- we want the parent id of the item just inserted
    SELECT @Supervisor_ID = User_ID FROM @tmpStack WHERE Supervision_ID = @Supervision_ID
  END
END

-- And update all the Items in Hier_Dept
-- in the original hierarchy table
UPDATE e
SET Lft = ts.Lft,
rgt = ts.rgt
FROM tbl_Personnel_Supervisors e
INNER JOIN @tmpStack ts
ON ts.User_ID = e.User_ID

GO

Answer : convert adjacency model table into nested set model table

MSDE IS SQL Server.
Do you regard SQL Server as being as robust as Access?   (dont laugh)(:-)

Pete

You can go to Community Support to ask for a  to be moved.