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I'm trying to write a script to return duplicate values based on a set of parameters if they repeat twice. For example in my text file I have this setup:
Now if the Last Name, First Name, and DOB repeat I want it too return both those lines and continue on, I know awk can do this, but it doesn't seem to work right.
awk '!seen[$4,$5]++ > 1' DemoDATA.txt