Displaying a copyright statement in the footer of your web pages is easily done with something like this:

Copyright &copy; <?php echo date('Y'); ?> Digging into WordPress

This code will output the following text:

Copyright © 2009 Digging into WordPress

I think most of us are familiar with this technique, as it would be a total pain to manually update the copyright date on all of your sites every year.

But what if you want to display your site’s copyright statement as a range of dates instead of just the current year? Many sites do this, and I am guessing that they do something like this in their source code:

Copyright &copy; 2008 - <?php echo date('Y'); ?> Digging into WordPress

While this method certainly works, it would be better to automate the process and have the range of dates displayed dynamically. This would be especially helpful for publicly released themes, where you want to minimize the amount of “fiddling” involved with the setup and configuration process.

To display a copyright as a range of dates for your theme, add the following function to your theme’s functions.php file:

<?php // display range of dates for copyright @ digwp.com
function copyrightDate() {
	global $wpdb;
	$copyright_dates = $wpdb->get_results("
		SELECT 
			YEAR(min(post_date_gmt)) AS firstdate, 
			YEAR(max(post_date_gmt)) AS lastdate 
		FROM 
			$wpdb->posts
	");
	if($copyright_dates) {
		$copyright = "Copyright &copy; " . $copyright_dates[0]->firstdate;
		if($copyright_dates[0]->firstdate != $copyright_dates[0]->lastdate) {
			$copyright .= '-' . $copyright_dates[0]->lastdate;
		}
		echo $copyright . "&nbsp;" . get_bloginfo('name');
	}
}
add_filter('wp_footer', 'copyrightDate');
?>

That’s all there is to it. Nothing else needs to be done in order for this code to output the something similar to the following:

Copyright © 2008-2009 Digging into WordPress

If your site is less than a year old, the function will simply print a single-year copyright date:

Copyright © 2009 Digging into WordPress

By default, this function will display this information wherever the following hook is located in your theme:

<?php wp_footer(); ?>

If this hook is not present, of if you would like to customize the location of the copyright statement, simply call the function anywhere in your theme with the following tag:

<?php copyrightDate(); ?>

Depending on your theme setup, if you call the function directly, you may want to comment out the last line (i.e., add_filter()) in the function itself to prevent duplicate output.

References

[1] http://www.copyright.gov/help/faq/faq-general.html
[2] Unless you wish to bring a lawsuit for infringement of a U.S. work.
[3] Source: Intellectual Property: Patents, Trademarks, Copyrights and Trade Secrets

© 2009 Digging into WordPress | Permalink | 12 comments | Add to del.icio.us | Post tags: copyright, date, echo, footer

• The number of database queries that your page is making
• How many seconds it took your server to complete those queries

The number of database queries is generated from the following WordPress template tag:

<?php echo get_num_queries(); ?>

This is a very straightforward, parameter-less function that will output the number of database queries required to generate all of the dynamic content on your page. Then, the amount of time required to complete those “x” number of queries is provided by this template tag:

<?php timer_stop(7); ?>

As shown here, this function accepts a parameter that specifies the number of significant digits to be used for the output. Here, the number “7” tells the function to output the query-processing time to seven digits of accuracy. So we would see a number like this:

.0173788

When used together, these two WordPress functions provide an instant snapshot into the basic performance of your web pages. Here is an example of the statistical output generated by these tags working together:

33 queries in 0.333 seconds

Many of you have probably seen this information while snooping around the far corners of your favorite websites. Lots of people use this code, although not everybody uses it the same way. Here are three great techniques for including this information on your site.

Show it off publicly
If you are particularly proud of your server’s performance and would like to show off these stats to your visitors, place the following code into the footer or sidebar of your active theme:

<p><?php echo get_num_queries(); ?> queries in <?php timer_stop(1,3); ?> seconds</p>

Display it under the hood
If you would rather not clutter your design with extraneous information, but still want to keep an eye on these stats, you can “comment out” the output string so that it only appears as a comment in the source code of your web pages. To do so, place this code in your theme’s footer.php file:

<!-- <?php echo get_num_queries(); ?> queries in <?php timer_stop(1,3); ?> seconds -->

Keep it private
Last but not least, if you don’t like the idea of sharing this information with the entire world, you can limit its display to logged-in administrators only with the following code:

<?php if (current_user_can('level_10')) {

	echo '<!-- ' . get_num_queries() . ' queries in ' . timer_stop(0,3) . ' seconds -->';

} ?>

This tells WordPress to check if the current user is an Administrator (i.e., Level-10 privileges) and if so output the statistical information to the web page. Here we have restricted the display of this information to the source code, but you can change this to display on the page itself by replacing the “<!-- ” and “ -->” with “<p>” and “</p>”, respectively.

Update: note that there are two ways to display the timer_stop output on the page. The timer_stop() function actually accepts two parameters, $display and $precision. Here are their default values:

<?php timer_stop($display = 0, $precision = 3) ?>

As you might guess, $display is an integer that determines whether or not the function outputs the results to the web page (1 for output, 0 for no output). Thus, you may either use 0 for the $display parameter and explicitly echo the results; or else you may use 1 for the $display parameter and omit the explicit echo.

You can see the latter method in the first two examples in this post, and the former in the third. Thanks to Rarst for pointing this out :)

© 2009 Digging into WordPress | Permalink | 26 comments | Add to del.icio.us | Post tags: database, footer, statistics, tricks

<p>
   &copy; <?php echo date("Y"); echo " "; echo bloginfo('name'); ?>
</p>

The year will always be the current year, based on your server’s set time. The text will come directly from the Blog Title setting in Settings > General.

© 2009 Digging into WordPress | Permalink | 3 comments | Add to del.icio.us | Post tags: copyright, date, echo, footer