title: I need to use a like query in mongo php
body: <p>I have used this query in shell. It worked fine. If I use it in php, it shows me an error</p>
  
  <pre><code>&lt;?php
  $m = new Mongo();
  $db = $m-&gt;foo;
  $collection = $db-&gt;base;
  $query = array( "ro" =&gt; '/^a/' );
  $cursor = $collection-&gt;find($query);
  
  foreach ($cursor as $obj) {
      echo $obj["ro"] . "&lt;br/&gt;";
  }
  </code></pre>
  
  <p>I am not sure, will <code>db.base.find({"ro": /^a/}).limit(10);</code> query work in php??</p>