How to Create Plugin for Queries to External Database

Is this post in the correct sub-forum, Plugins and hacks? Should it be moved to another place on this forum?

I am trying the page template approach. Seems the right one. This WP site is on a server only accessible on my home LAN.

But I am not sure accessing the external database (via wpdb class) is working for me. Suggestions on how to test that wpdb class usage is/is not working please. See what I have tried so far —

<?php
/**
 * Template Name: Page qryVids Test
 * Description: Test access to the videodb database
 * This is a page template file to reside in the Theme's page templates
 *
 * Created: March 2015 -- Jim
 * HISTORY:
 *   12 Mar 2015 -- created for use within WP
 *
 *
 */

get_header(); ?>

<div id="primary" class="site-content">
	<div id="content" role="main">

<!-- ----------  Begin my custom WP Page Template code  ------------- -->
		<p>This is HTML text</p>

<?php
	echo ("<p>this is PHP test text</p>");			

    echo "<p>qryVids database: " . get_option('qryvids_dbname') . "</p>";
	$viddb = new wpdb(get_option('qryvids_dbuser'),get_option('qryvids_dbpwd'), get_option('qryvids_dbname'), get_option('qryvids_dbhost'));
	$viddb->show_errors();

		$videocnt = $viddb->get_var("SELECT count(*) FROM videodata");
		echo "<p>Number of videos in the database = $videocnt </p>";

        echo "<p>Last Query: $viddb->last_query </p>";
		echo "<p>Last Error = $viddb->last_error </p>";

?>
<br>
<br>
<br>
<br>
<br>

<br>
<br>
<br>

<!-- ----------  End of my custom code  ----------------- -->
	</div> <!-- end of #content -->
</div> <!-- end of #primary -->
<?php get_footer(); ?>

The output on the WP page is:

This is HTML text

this is PHP test text

qryVids database: videodb

Number of videos in the database =

Last Query:

Last Error =

There should be 921 records reported in the Select count(*), why nothing?
No query shows in the last_query varable, why?
I have no confidence there are no errors, but at least WP doesn’t think there are any.