Are you trying to compare a list of ITEMS associated with each ID ?

How complex is the "compare" ? Is it just checking if the item exists in the values for the other ID ?

These types of queries are usually much more efficient and readable when done in SQL. using something like : 

  SELECT item from mytable
  WHERE ID = '555549'
  AND  item NOT IN 
     (SELECT item from mytable where ID='560834');

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Of course, you can use perl to build the query and subquery.

Update:

If you really want to examine CURRENT, PREVIOUS and NEXT items in an array, consider using Array::Iterator::BiDirectional.

        If your eyes hurt after you drink coffee, you have to take the spoon out of the cup.
              -Norm Crosby

In reply to Re: compare previous and present hash key values by NetWallah
in thread compare previous and present hash key values by undisputed

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