Unix "sort" command for a CSV file

awk to the rescue! with decorate/sort/un-decorate pattern.

$ awk -F, '{t=$2; sub(/.+ /,"",t); print t"\t"$0}' file | sort | cut -f2-

"29 January 2016 19:33 EST","Mary Z Allen",...
"22 February 2016 12:08 EST","Shawn Baker",...
"01 February 2016 16:29 EST","Kendra A Zimmerman",...

print the last word of the second field as key, sort and remove the dummy key.

No. The sort command can split into fields, so if you just wanted to sort by name, you could do something like sort -t, -k2. But for this, what you'll have to do is to split the lines out. Here's a very simplistic example of extracting the thing you want to sort upon, prepending it to the line, sorting on only the first field, then removing that field.

user@machine[/home/user/dev]
$ cat testfile
"22 February 2016 12:08 EST","Shawn Baker",...
"29 January 2016 19:33 EST","Mary Z Allen",...
"01 February 2016 16:29 EST","Kendra A Zimmerman",...
user@machine[/home/user/dev]
$ paste <(cut -d, -f2 testfile | awk '$0=$NF') testfile | sort -k1,1 | cut -f2-
"29 January 2016 19:33 EST","Mary Z Allen",...
"22 February 2016 12:08 EST","Shawn Baker",...
"01 February 2016 16:29 EST","Kendra A Zimmerman",...

Note that this code to extract the desired field makes the bad assumption that the the first and second fields won't contain a comma: cut -d, -f2 testfile | awk '$0=$NF' If they may, then you'll want to replace it with something smarter. The rest of the code should be fine, as paste and cut defualt to tabs, and sort/awk are using whitespace.

You can use sed to copy the lastline in front of your line. That way sorting is easy and you only need to delete the extra data. The sed command will need to look for strings without a double quote using [^"]*, resulting in

sed 's/\("[^"]*","[^"]* \)\([^"]*"\)/\2=\1\2/' testfile | sort | cut -d= -f2