What is the difference between limit(1) and range(0, 1)?

Question

In a query I tried using limit(1); I got a WSOD, but when I use range(0,1) I don't get any WSOD.

What is the basic difference between limit(1) and range(0, 1)?

Answer 1

Base difference is that range is a method of SelectQuery class, and limit isn't.

Some APIs can extend SelectQuery and add limit. For example $query->extendQuery('PagerDefault') will return object of PagerDefault class that has limit method defined.

It may result in a syntax looking like limit() is invoked on SelectQuery, when in fact it isn't:

$query = db_select('node', 'n')
      ->fields('n')
      ->condition('type','problem','=')
      ->extend('PagerDefault')
      ->limit(20);