Hi Zu,
There are documents posted by Mr. Jogeswara Rao Kavala which give all information about it.Please see these posts:
Alias Tables in Infosets and QuickViews
10 Useful Tips on Infoset Queries
ALV Report on Catalog Profile and Catalogs & Codes - (Infoset way)
hope it helps.
Br
Saurabh
