title: Difference between PDO->query() and PDO->exec()
body: <p>I see that there is both <code>PDO::query()</code> and <code>PDO::exec()</code>. In the page that was linked, it appears that <code>PDO::query()</code> is used for <code>SELECT</code> statements ONLY, and <code>PDO-&gt;exec()</code> is used for <code>UPDATE</code>,<code>INSERT</code>,<code>DELETE</code> statements. Why do these methods exist and when to use them?</p>