Linux shell sort file according to the second column?

Question

I have a file like this:

FirstName, FamilyName, Address, PhoneNumber

How can I sort it by FamilyName?

Answer 1

sort -nk2 file.txt

Accordingly you can change column number.

Answer 2

If this is UNIX:

sort -k 2 file.txt

You can use multiple -k flags to sort on more than one column. For example, to sort by family name then first name as a tie breaker:

sort -k 2,2 -k 1,1 file.txt

Relevant options from "man sort":

-k, --key=POS1[,POS2]

start a key at POS1, end it at POS2 (origin 1)

POS is F[.C][OPTS], where F is the field number and C the character position in the field. OPTS is one or more single-letter ordering options, which override global ordering options for that key. If no key is given, use the entire line as the key.

-t, --field-separator=SEP

use SEP instead of non-blank to blank transition

Answer 3

To sort by second field only (thus where second fields match, those lines with matches remain in the order they are in the original without sorting on other fields) :

sort -k 2,2 -s orig_file > sorted_file

Answer 4

FWIW, here is a sort method for showing which processes are using the most virt memory.

memstat | sort -k 1 -t':' -g -r | less

Sort options are set to first column, using : as column seperator, numeric sort and sort in reverse.