@ankit (or anyone else who thinks this type of "numbering" is a good idea),

Let me tell you why BASE 26 "numbering" like this is SO bad that it'll likely get your company sued... try the following code with your choice of classic "3 and 4 letter" swear words and see what you get...

SELECT * FROM #MyHead WHERE Base26ID LIKE '%CRAP%'

Every soccer mom and little old lady in the world will be out to get you and your company if these numbers ever are exposed publicly.;-)