Hi Giridhar,
Are you using FCC at sender ?
Is your file contain one Record per Line? How many lines can the file contain?
How many files is expected to be received per day?
If your file contains One Line = One record and if you are OK to process the file Line by Line, then you can read the Flat file in FCC line by Line (1 new Msg will get created in PI for each Line). For settings check the following link:
How to split a message into chunks in a file to proxy interface
Regards,
Azhar