set multiple select list options to selected from query
<p>I have a field named 'majors' which contains a string of integers seperated by commas.  This field is populated from a multiple select list on insert query using the following variable:</p>

<pre><code>$majors_string = implode(",", $majors);
</code></pre>

<p>Now on the edit page, I want to have those values set the options in the same list.  Part of the problem is that the list is generated dynamically using:</p>

<pre><code>&lt;select name="majors[]" size="9" multiple="multiple" id="majors"&gt;
          &lt;?php 
$query = mysql_query("SELECT * from major ORDER BY title ASC");
for($i=0;$i&lt;mysql_num_rows($query);$i++) {
$row=mysql_fetch_assoc($query);
?&gt;
          &lt;option value="&lt;?php echo $row['major_pk']; ?&gt;"&gt;&lt;?php echo $row['title']; ?&gt;&lt;/option&gt;
          &lt;?php 
}
?&gt;
        &lt;/select&gt;
</code></pre>

<p>On the initial query on the edit page, I have:</p>

<pre><code>$query_topic = "SELECT * FROM topic WHERE topic_pk = '$topic_pk'";
$result_topic = mysql_query($query_topic, $connection) or die(mysql_error());
$row_topic = mysql_fetch_assoc($result_topic);

$retrieved_majors = explode(",", $row_topic['majors']);
</code></pre>

<p>But I'm unsure as to set the options in the multiple list to the values in array $retrieved_majors.  </p>

<p>Thanks for any help!</p>
