Hi I'm looking for a software that can merge two CSV files based on certain primary fields. For example, suppose I have 1 file with the fields email, twitter handle, name and another file with fields email, facebook ID, website. I want to merge the fields that match based on "email" (or another field). In this case, if both files contain the same email we add all other fields (twitter handle, name, facebook ID, website) to new file so all info is contained in a single file. Which software can do this?