MySQL Shell's \edit command opens a command in
      the default system editor for editing, then presents the edited
      command in MySQL Shell for execution. The command can also be
      invoked using the short form \e or key
      combination Ctrl-X Ctrl-E. If you specify an
      argument to the command, this text is placed in the editor. If you
      do not specify an argument, the last command in the MySQL Shell
      history is placed in the editor.
    
      The EDITOR and VISUAL
      environment variables are used to identify the default system
      editor. If the default system editor cannot be identified from
      these environment variables, MySQL Shell uses
      notepad.exe on Windows and
      vi on any other platform. Command editing takes
      place in a temporary file, which MySQL Shell deletes afterwards.
    
When you have finished editing, you must save the file and close the editor, MySQL Shell then presents your edited text ready for you to execute by pressing Enter, or if you do not want to proceed, to cancel by pressing Ctrl-C.
      For example, here the user runs the MySQL Shell built-in report
      threads with a custom set of columns, then
      opens the command in the system editor to add display names for
      some of the columns:
    
\show threads --foreground -o tid,cid,user,host,command,state,lastwait,lastwaitl
\e
\show threads --foreground -o tid=thread_id,cid=conn_id,user,host,command,state,lastwait=last_wait_event,lastwaitl=wait_length