Wordpress - Count & Display Database Queries
You can paste this block of code in your currently active WordPress theme functions.php
file:
function wpse_footer_db_queries(){
echo '<!-- '.get_num_queries().' queries in '.timer_stop(0).' seconds. -->'.PHP_EOL;
}
add_action('wp_footer', 'wpse_footer_db_queries');
The above block of code, will render an HTML comment in the footer of your theme (before </body>
and </html>
, containing the number of database queries and how log they took to retrieve.
Add …
define( 'SAVEQUERIES', TRUE );
… to your wp-config.php
, and inspect $wpdb->queries
at shutdown
. That is the latest hook and the only one after which no queries are fired. Plus, it works on wp-admin/
too.
Sample code as a plugin:
<?php
/**
* Plugin Name: T5 Inspect Queries
* Description: Adds a list of all queries at the end of each file.
*
* Add the following to your wp-config.php:
define( 'WP_DEBUG', TRUE );
define( 'SAVEQUERIES', TRUE );
*/
add_action( 'shutdown', 't5_inspect_queries' );
/**
* Print a list of all database queries.
*
* @wp-hook shutdown
* @return void
*/
function t5_inspect_queries()
{
global $wpdb;
$list = '';
if ( ! empty( $wpdb->queries ) )
{
$queries = array ();
foreach ( $wpdb->queries as $query )
{
$queries[] = sprintf(
'<li><pre>%1$s</pre>Time: %2$s sec<pre>%3$s</pre></li>',
nl2br( esc_html( $query[0] ) ),
number_format( sprintf('%0.1f', $query[1] * 1000), 1, '.', ',' ),
esc_html( implode( "\n", explode(', ', $query[2] ) ) )
);
}
$list = '<ol>' . implode( '', $queries ) . '</ol>';
}
printf(
'<style>pre{white-space:pre-wrap !important}</style>
<div class="%1$s"><p><b>%2$s Queries</b></p>%3$s</div>',
__FUNCTION__,
$wpdb->num_queries,
$list
);
}
Update
After thinking a little bit longer about it I have written another plugin more suited for my needs – and probably yours if you prefer the console.
<?php
/**
* Plugin Name: T5 Log Queries
* Description: Writes all queries to '/query-log.sql'.
* Plugin URI: http://wordpress.stackexchange.com/a/70853/73
* Version: 2012.11.04
* Licence: MIT
*/
add_filter( 'query', 't5_log_queries' );
/**
* Write the SQL to a file.
*
* @wp-hook query
* @param string $query
* @return string Unchanged query
*/
function t5_log_queries( $query )
{
static $first = TRUE;
// Change the path here.
$log_path = apply_filters(
't5_log_queries_path',
ABSPATH . 'query-log.sql'
);
$header = '';
if ( $first )
{
$time = date( 'Y-m-d H:i:s' );
$request = $_SERVER['REQUEST_URI'];
$header = "\n\n# -- Request URI: $request, Time: $time ------------\n";
$first = FALSE;
}
file_put_contents( $log_path, "$header\n$query", FILE_APPEND | LOCK_EX );
return $query;
}
Track the file with tail
(available on Windows if Git is installed):
$ tail -f query-log.sql -n 50