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Functions

Compare two CSV files, discarding any repeated lines

Terminal - Compare two CSV files, discarding any repeated lines
cat foo.csv bar.csv | sort -t "," -k 2 | uniq
2009-02-19 20:23:03
User: rafeco
Functions: cat sort
2
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Compare two CSV files, discarding any repeated lines

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.

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Alternatives

There are 3 alternatives - vote for the best!

Terminal - Alternatives

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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

Comment by kst 440 weeks ago

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