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q

In this example we will install q which allows to run SQL directly on CSV or TSV files.

q's purpose is to bring SQL expressive power to the Linux command line by providing easy access to text as actual data, and allowing direct access to multi-file sqlite3 databases. q is a terminal-based application without a graphical user interface.

Info

q can be installed in any workspace. We will use Codeserver workspace v.5.0 in this example.

Install

The first thing to do is to download the q binary package. Open workspace terminal and execute the following commands

$ cd /tmp 
08:01:30 with <font color="#FDEB61">abc</font> in <font color="#37E6E8">/tmp</font> <font color="#98E242">➜</font>

$ wget https://github.com/harelba/q/releases/download/v3.1.6/q-text-as-data-3.1.6-1.x86_64.deb 

q-text-as-data-3.1.6-1.x86_64.deb   100%[==================================>]  26.36M  1.72MB/s    in 9.2s    

2022-09-05 08:03:32 (2.87 MB/s) - ‘q-text-as-data-3.1.6-1.x86_64.deb’ saved [27641912/27641912]

Now we can install q

$ sudo dpkg -i q-text-as-data-3.1.6-1.x86_64.deb

Selecting previously unselected package q-text-as-data.
(Reading database ... 35238 files and directories currently installed.)
Preparing to unpack q-text-as-data-3.1.6-1.x86_64.deb ...
Unpacking q-text-as-data (3.1.6) ...
Setting up q-text-as-data (3.1.6) ...

You can check if q is installed 

$ q 

q version 3.1.6
Python: 3.8.11 (default, Jul 24 2021, 23:08:48) // [Clang 12.0.1 ]
Copyright (C) 2012-2021 Harel Ben-Attia (harelba@gmail.com, @harelba on twitter)
http://harelba.github.io/q/

Must provide at least one query in the command line, or through a file with the -q parameter

Use

Let's create a dummy .csv file, and try querying it with q

$ seq 1 1000000 > /home/project/myfile.csv
$ tail -n 3 /home/project/myfile.csv 

999998
999999
1000000

We have printed last 3 rows, and see that the .csv file is generated.

Let's query it now with q 

$ cd /home/project
08:01:33 with <font color="#FDEB61">abc</font> in <font color="#37E6E8">~p</font> <font color="#98E242">➜</font>

$ q "select sum(c1),count(*) from myfile.csv where c1 % 3 = 0"

166666833333 333333

Check out more examples on the q documentation website.