in reply to i need to join two fields in .csv file??

Sure, here you go Use Text::CSV or Text::xSV

Examples at

 [CSV hash ] CSV hash
Best way to match a hash with large CSV file
perl hash to CSV using Text::CSV_XS
Issue parsing CSV into hashes?
Veriable Length Array/Hash derived from CSV to populate an XML
extracting data from CSV files and making hash of hashes
Re^2: build hash from csv file
Encoding a hash in perl before saving it as a CSV file
hash from CSV-like structure
Read the csv file to a hash....
Parsing CSV into a hash
build hash from csv file
Converting a CSV list to a list of hashrefs naming the fields