Compare two CSV files, discarding any repeated lines

cat foo.csv bar.csv | sort -t "," -k 2 | uniq
The value for the sort command's -k argument is the column in the CSV file to sort on. In this example, it sorts on the second column. You must use some form of the sort command in order for uniq to work properly.

2
By: rafeco
2009-02-19 20:23:03

What Others Think

I was about to suggest a shorter alternative: sort -u -t "," -k 2 foo.csv bar.csv but I realized that sort's "-u" option only checks the comparison key for uniqueness; what you want here is to check the entire line. But you can still avoid the UUOC (useless use of cat): sort -t "," -k 2 foo.csv bar.csv | uniq And the quotation marks around the comma aren't necessary, but they don't hurt anything
kst · 539 weeks and 5 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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