title: Grep logs from the last hour
body: <p>I am trying to grep logs that happened in the last hour, time format is like this:
  <strong>2020-11-01 18:46:56</strong>.036</p>
  <p>I tried to run this:</p>
  <pre><code>grep &quot;^$(date -d -1 hour +'%Y-%m-%d %H')&quot; postgresql-Mon.log | tail -n 100
  </code></pre>
  <p>but that doesn't work. Also how do I use the tail command without -n? I want to grep from bottom to top but to get all the logs from the last hour not only 100.</p>
  <p>Help please :&gt;</p>
  <p>I know there are other ways doing it but I need it with grep command</p>