Change Default Editor in Debian

My favourite editor is vim in Linux. I am very comfortable with it. But when I need to do some come some configuration(e.g. crontab -e), operating system opens it with default editor which is generally nano. This is annoying to me. Therefore, I generally change default editor with the following very simple step to vim:

# sudo update-alternatives --config editor

Following table has printed.

There are 3 choices for the alternative editor (providing /usr/bin/editor).

  Selection    Path                Priority   Status
------------------------------------------------------------
* 0            /bin/nano            40        auto mode
  1            /bin/nano            40        manual mode
  2            /usr/bin/vim.basic   30        manual mode
  3            /usr/bin/vim.tiny    10        manual mode


Press enter to keep the current choice[*], or type selection number:

Write <2> and hit the enter.

Result print:

update-alternatives: using /usr/bin/vim.tiny to provide /usr/bin/editor (editor) in manual mode.

Now, default editor in the system is vim. To see the effect, run command crontab -e. It will be opened by vim.