Is there a way to 'uniq' by column?
I have a .csv file like this:
[email protected],2009-11-27 01:05:47.893000000,example.net,127.0.0.1
[email protected],2009-11-27 00:58:29.793000000,example.net,255.255.255.0
[email protected],2009-11-27 00:58:29.646465785,example.net,256.255.255.0
...
I have to remove duplicate e-mails (the entire line) from the file (i.e. one of the lines containing [email protected] in the above example). How do I use uniq on only field 1 (separated by commas)? According to man, uniq doesn't have options for columns.
I tried something with sort | uniq but it doesn't work.
Answer
sort -u -t, -k1,1 file
-ufor unique-t,so comma is the delimiter-k1,1for the key field 1
Test result:
[email protected],2009-11-27 00:58:29.793000000,xx3.net,255.255.255.0
[email protected],2009-11-27 01:05:47.893000000,xx2.net,127.0.0.1