title: SQlite: Select rows within a specific time range, ignoring the date
body: <p>I have a table called <code>messages</code> that stores messages from a chat with the following columns: <code>username, message, datetime</code>, where the type of datetime is TEXT and it is stored in the following format: "yyyy/MM/dd hh:mm:ss". I want to retrieve the average count of rows within a specific time range, without bothering with the date. For instance:</p>
  
  <pre><code>SELECT avg(count(message))
  FROM messages
  WHERE datetime &lt; "2016/mm/dd 13:00:00" AND
        datetime &gt; "2016/mm/dd 12:00:00"
  </code></pre>
  
  <p>Is there some operator that allows any character to take the place of "mm" and "dd". Essentially, I am trying to construct a query that retrieves the average amount of messages within a specific time range, not the amount of messages on a specific date.</p>