Hi Marker: I have already create a folder, name "Data", in which, i have already create three table for testing. So, if you need to test my program, please put the files, like .slc .apd in the folder of "Data" Because my program is developed under the Mac, so, maybe there would be a little problem. for example: I write all the file back to the "Data" folder, in Mac, the path separator is "/", but windows would be "\" so if any problem, please let me know, i will do the demo face to face. I am so sure my program work perfectly. the only small work i have not finish is the Haskell checking problem: if you offer me the CustDB or SalesDB or OrderDB file with some corrupted record, my haskell program will not work but for the three tables which without any corrupted record, it will work perfectly. the other problem is that, as i mentioned, I program this under the Unix. In mac, we dont have the exe file. so i generate .exe file under windows, but if there is any problem in the haskell you can run it in terminal the command line is: runhaskell Report.hs runhaskell GroupByReport.hs or, my source code is in the Haskell Folder any problem, please let me know, i am sure my program work perfectly. thanks