title: Issue when compare a value in column with number
body: <p>I have a issue, i do not know this is bug or not, could you please help to analyze problem.
  My table hs a column ‘contents’ with type ‘varchar’.
  when i insert value to this column (ex: xyz x#1, y, z can be any number) then i do query </p>
  
  <pre><code>$this-&gt;find()-&gt;where([‘content &gt;’ =&gt; ‘20’])-&gt;toArray();
  </code></pre>
  
  <p>The query will return xyz for me. that is my expectation.
  but when i insert value like 1yz (y, z can be any number) then i do query </p>
  
  <pre><code>$this-&gt;find()-&gt;where([‘content &gt;’ =&gt; ‘20’])-&gt;toArray();
  </code></pre>
  
  <p>The query will return empty array.
  I have tried with many value like 123; 145; 134; 1678 but it returned same result.
  Do you had the same situation? please give me an advice.
  Thank you very much.
  (Ps: i have tried with cakephp 3.6 and cakephp 1.2)</p>