I prefer “1=0 OR 1=1”, because when you delete all conditions you can keep 1=0 out of selection and it decays into a no-op rather than destroying a table:

  DELETE FROM table
  WHERE 1=0[ OR 1=1
    AND age > 21
    AND xyz = 'abc']
  ;

Brackets designate selection bounds before text deletion. The above just safely does nothing after you hit DEL.

Without that you’d have to delete whole [WHERE…], which leaves a very dangerous statement in the code.