UNIX for Dummies Questions & Answers

Hi
I have a tab delimited file with 3 fields. I need to sort this file on the first field and remove all the records where the first field has dulplicates. For eg my file is

133|arrfdfdg|sdfdsg
234|asfsdgfs|aasdfs
133|affbfsde|dgfg

When this file gets sorted I need the result to be
234|asfsdgfs|aasdfs

So if there are duplicate entries in the first column, all those records should be removed. How can I do this in unix? I am able to sort it to get single records based on unique first field using

sort -u -k 1,1 filename

but this is not what I am looking for. Any help will be appreciated!

try:

Code:

sort -u -t=| -k1.1,1.8 filename

To just print non-repeated lines in the file turns out to be a bit of a pain. The uniq command would do it but only if the key is on the right hand side of the line, so I've put it there.

The code sorts the file on the first column (delimited by pipes) then appends the key to the end of the line uses and uses uniq to remove line with non-repeated keys before stripping off the added key!

Looks a bit klunky - I'm sure that someone could do something more elegant

Code:

Code
sort -t'|' -k1,1 < yourfile.txt | while read x
do
  print $x ${x%%'|'*}
done | uniq -f1 -u | cut -d' ' -f1

cheers