I rarely use custom tables, but in one of my last projects it was necessary. One thing that I learned was that you need to register the table with the $wpdb object. Something like this May help you out:
function my_register_custom_database_tables() {
global $wpdb;
$wpdb->my_table_name = $wpdb->prefix . 'my_table_name';
}
add_action( 'init', 'my_register_custom_database_tables' );
Thread Starter
Ryan
(@rfrankel)
Thanks. I was able to successfully add the tables and register them in the initialization of the plugin. The problem seems to come from writing to the tables during an AJAX call.
It is possible that the issue stems from a bug in the Ajax implementation. Using the code you posted above, can you write to the table with no Ajax? How do you have your ajax callbacks set up? Please post code to http://wordpress.pastebin.com if it is long.
Thread Starter
Ryan
(@rfrankel)
Here is my code for the Admin of the plugin:
Options Page
And here is the relevant code from the called PHP file:
Called File
Many thanks for any help Michael!
Thread Starter
Ryan
(@rfrankel)
As an update…from http://codex.wordpress.org/AJAX_in_Plugins:
——–
First, add some javascript that will trigger the AJAX request:
<?php
add_action('admin_head', 'my_action_javascript');
function my_action_javascript() {
?>
<script type="text/javascript" >
jQuery(document).ready(function($) {
var data = {
action: 'my_special_action',
whatever: 1234
};
// since 2.8 ajaxurl is always defined in the admin header and points to admin-ajax.php
jQuery.post(ajaxurl, data, function(response) {
alert('Got this from the server: ' + response);
});
});
</script>
<?php
}
Then, set up a PHP function that will handle that request:
<?php
add_action('wp_ajax_my_special_action', 'my_action_callback');
function my_action_callback() {
global $wpdb; // this is how you get access to the database
$whatever = $_POST['whatever'];
$whatever += 10;
echo $whatever;
die();
}
—–
Is this how it should be done? I can see there are some differences in my implementation, mostly that it looks like this is triggered using some WP hook instead of how I did it with a user clicking. To me though, it looks like the example would fire everytime the page is loaded.
Once again any info would be greatly appreciated.
Does the WordPress environment exist in Called File? From what you posted, it does not look like it does. Ajax calls are best handled in WordPress using /wp-admin/admin-ajax.php Two really great places to start are:
http://codex.wordpress.org/AJAX
http://www.wphardcore.com/2010/5-tips-for-using-ajax-in-wordpress/
Sorry, I was still typing when you made your last post 🙂 Yes this is the proper way to handle Ajax calls. Most likely your problem stems from not having the $wpdb global defined in the original callback script. Using admin-ajax.php should solve this.
Thread Starter
Ryan
(@rfrankel)
Thanks Michael! I will take a look at that and make the required mods to try and get this going.
