title: MySQL errors in php script
body: <p>We are developing a helpdesk system at our workplace (highschool).
  We are gonna publish some usermanuals on the site up to a database.</p>
  
  <pre><code>$sql = "INSERT INTO usermanual (title, link, slug) VALUES ('$title', '$link', '$slug')";
  </code></pre>
  
  <p>This is our code to get from the form:</p>
  
  <pre><code>&lt;form action="inc/publish-manual.php" method="post" accept-charset="ISO-8859-1"&gt;
      &lt;p&gt;
          &lt;label for="Title"&gt;Tittel:&lt;/label&gt;
          &lt;br&gt;
          &lt;input type="text" name="title" id="title"&gt;
      &lt;/p&gt;
      &lt;p&gt;
          &lt;label for="Link"&gt;Link til brukerveiledning:&lt;/label&gt;
          &lt;br&gt;
          &lt;input type="text" name="link" id="link"&gt;
      &lt;/p&gt;
      &lt;p&gt;
          &lt;label for="Slug"&gt;Slug:&lt;/label&gt;
          &lt;br&gt;
          &lt;input type="text" name="slug" id="slug"&gt;
      &lt;/p&gt;
      &lt;input type="submit" value="Publiser"&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p></p>
  
  <p>When we run this we only get an error saying:</p>
  
  <pre><code>ERROR: Was not able to execute INSERT INTO usermanual (title, link, slug) VALUES ('test', 'http://gauldal.vgs.no/upload/Gauldal/Bilder/Brukerveiledninger-IKT/Bruke%20Larermentor.pdf', 'test')
  </code></pre>
  
  <p>When we run the SQL in the database it works, but not from our script.
  We have been looking at this for a long time, and now we need a pair of fresh eyes to see where the mistake is.</p>