title: Can an integer column be null?
body: <p>I made an <code>integer</code> column that is <code>null</code> by default but when I put empty double quotes <code>""</code> it gives this error:</p>
  
  <blockquote>
  <pre><code>ERROR: invalid input syntax for integer: ""
  </code></pre>
  </blockquote>
  
  <p>Does the <code>integer</code> column have to be <code>0</code> then?</p>
  
  <p>I am using Java to send the query to the database.</p>