Ubuntu: How to sort file contents using command ?

In this article, I will share my understanding of sort command with some examples. One important point to notice is that the file contents must be on separate line. If file contains only single line then we are not able to observe the effect of sort command. Before jumping directly to examples, here are some of its variations

To sort file contents                             : sort filename.txt

To sort according to column contents   : sort –k (column number) filename

To sort in reverse order                       : sort –r filename

To remove duplicates while sorting      : sort –u filename

•  Sorting numeric contents

           Suppose file contains only numeric data then file contents are sorted in ascending order of integer values as shown below.

$ cat file

015

004

016

009

003

018

002

020

$ sort file

002

003

004

009

016

018

020

•   Sorting alphabetic contents

            Suppose file contains only alphabetic data then file contents are sorted alphabetically as shown below.

$ cat file

Ashish Gaigole

Siyaram Vishwakarma

Deepak Jaiswal

Dashrath Sharma

$ sort file

Ashish Gaigole

Dashrath Sharma

Deepak Jaiswal

Siyaram Vishwakarma

•  Sorting alpha-numeric contents

           In case file has both numeric and alphabetic data then first all numeric data is sorted in ascending order followed by alphabetic data.

$ cat file

Ashish Gaigole

Siyaram Vishwakarma

Deepak Jaiswal

Dashrath Sharma

015

016

004

009

$ sort file

004

009

015

016

Ashish Gaigole

Dashrath Sharma

Deepak Jaiswal

Siyaram Vishwakarma

•  Sorting file contents according to particular column values

$ cat file

Ashish Gaigole 016 F-42

Siyaram Vishwakarma 015 F-43

Deepak Jaiswal 009 F-44

Dashrath Sharma 004 F-41

$ sort –k 3 file  : file is sorted according to third column in file.

Dashrath Sharma 004 F-44

Deepak Jaiswal 009 F-41

Siyaram Vishwakarma 015 F-43

Ashish Gaigole 016 F-42

$ sort –k 4 file  : file is sorted according to fourth column in file.

Deepak Jaiswal 009 F-41

Ashish Gaigole 016 F-42

Siyaram Vishwakarma 015 F-43

Dashrath Sharma 004 F-44