in reply to
Re^4: Command Line Hash to print things in common between two files
in thread Command Line Hash to print things in common between two files
As hinted at in one of the earlier replies, sometimes it's worth the effort to create a suitable utility to make a "simple" operation even simpler. It also allows you to add in some useful flexibility that will help to make your command line usage more effective with less typing.
I have to do a lot of "join"-like operations (actually, things like intersections, unions, and xors) on pairs of arbitrary lists or tables that vary as to delimiters and locations of key fields, so I wrote this "general purpose" tool: cmpcol. You haven't shown any samples of your data yet, so I don't know whether this tool might be useful to you, but I've had occasion to use it (and be glad to have it) just about every day since I wrote it.