Question

I have a csv file with 4 attributes in each line, delimited by comma. I’m trying to come up with a sed command to keep only the second attribute from each line. Any ideas on how to do it?

Answer 1

You’d be better off with cut:

cut -d "," -f 2 file.txt

If you want to remove dupes, and you don’t mind the order of the entries, simply do:

cut -d "," -f 2 file.txt | sort -u

And to extend to attrs 1 and to, simply use:

cut -d "," -f 1,2 file.txt | sort -u