How to sort multiple column with a column including date?

Question

I am trying to sort a file as following which has multiple columns, separated with comma, and one of the column has date with the following format mm/dd/yyyy.

$cat filename

AN1143,45.7,03/05/2012,
H9477,45.3,01/15/2010,
DN1222,45.1,03/05/1800,
J960,26.7,06/02,1990,
Z959,28.2,03/21/2016,
H12421,27.7,06/21/2000

My intention is to sort first based on the first column and then the third column which has the date. I tried the following command:

sort -t"," -k1,1 -k3,9n.3,10n -k3,1n.3,2n -k3,4n.3,5n filename 

but I faced this error any help with explanation is appreciated.

sort: stray character in field spec: invalid field specification â3,9n.3,10nâ

Answer 1

Try this instead:

sort -t, -k1,1 -k3.7n -k3.1,3.2n -k3.4,3.5n < filename

• There's no need to quote the comma delimiter
• The first sort-key definition uses column 1
• The second sort-key definition uses column 3's "year" field, sorted numerically
• The third sort-key uses column 3's "month" field, sorted numerically
• The fourth sort-key uses column 3's "day" field, sorted numerically

Sample run with an enhanced sample data file, showing the sorting:

Input:

AN1143,45.7,03/05/2012,
AN1143,45.7,02/05/2012,
AN1143,45.7,03/04/2012,
AN1143,45.7,03/05/2011,
H9477,45.3,01/15/2010,
DN1222,45.1,03/05/1800,
J960,26.7,06/02,1990,
Z959,28.2,03/21/2016,
H12421,27.7,06/21/2000

Output:

AN1143,45.7,03/05/2011,
AN1143,45.7,02/05/2012,
AN1143,45.7,03/04/2012,
AN1143,45.7,03/05/2012,
DN1222,45.1,03/05/1800,
H12421,27.7,06/21/2000
H9477,45.3,01/15/2010,
J960,26.7,06/02,1990,
Z959,28.2,03/21/2016,