record[3] is a bunch of numbers. I'm trying to find all unique entries. From what I've read a hash is the best way to do this, but I'm having trouble understanding how to assign a key to the record[3] value. Is a key like a primary key in a database? Where it is essentially a arbitrary unique number used to refer to the entry?

In reply to Re^4: Learning about hashes by molson
in thread Learning about hashes by molson

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