I have a text file that looks like this. 
item  group  entry_date
34     gr1    2003-03-02
12     gr1    1990-03-14
39     gr3    2002-04-11
66     gr4    2006-03-16
32     gr3    1998-02-13
90     gr1    2004-06-15
55     gr4    1999-06-15
etc ...

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What I need to do is to pull out the oldest entry for each group (gr1 etc) and print them all to a file. Is there some sort of date function or other easy way in whuch I can do this? Any suggestions appreciated.

In reply to Pulling out oldest entries from a text file by Angharad

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