Create tables on plugin activation

For some reason that I can’t figure out the code below is not creating the database table when the plugin is activated. There are no PHP errors and everything else appears to be working fine.

Can anybody spot anything obvious I have missed.

Thanks in advance

– Andy

<?php
/*

Plugin Name: Local Directory
Description: A directory for displaying local area businesses and resources.

*/

// Create The Class
if (!class_exists("local_directory_plugin")) {

	class local_directory_plugin {

			var $local_directory_db_version = "1.0";

			function local_directory_plugin() { //constructor
			}

			function local_directory_activate() { // Set up the database
				global $wpdb;
			    global $local_directory_db_version;

				$table_name = $wpdb->prefix . "directory_entries";

					   if($wpdb->get_var("show tables like '$table_name'") != $table_name) {

						  $sql = "CREATE TABLE IF NOT EXISTS " . $table_name . " (
							entry_id INT NOT NULL AUTO_INCREMENT ,
							name VARCHAR(45) NOT NULL ,
							description TEXT NOT NULL ,
							address_name_number VARCHAR(45) NOT NULL ,
							address_street VARCHAR(45) NULL ,
							address_town VARCHAR(45) NULL ,
							address_county VARCHAR(45) NULL ,
							address_postal_code VARCHAR(45) NOT NULL ,
							phone VARCHAR(45) NOT NULL ,
							fax VARCHAR(45) NULL ,
							url VARCHAR(255) NULL ,
							is_active TINYINT NOT NULL DEFAULT 0 ,
							owner_id INT NOT NULL ,
							category_id INT NOT NULL ,
							PRIMARY KEY  (<code>entry_id</code>) ,
							KEY fk_directory_entries_directory_categories (category_id ASC)
						);";

						  require_once(ABSPATH . 'wp-admin/includes/upgrade.php');
						  dbDelta($sql);

							// Add the options
							add_option("local_directory_db_version", $local_directory_db_version);
							add_option('local_directory_entries_per_page', '10');
							}

			} // end install function

			function local_directory_deactivate() { // Uninstall Local Directory

				//delete options
				delete_option('local_directory_entries_per_page');
				delete_option('local_directory_db_version');

			} // end install function

			function print_admin_summary_page() {	//Prints out the admin summary page

				include('admin/summary-page.php');	

			}//End function print_admin_summary_page()

			function print_admin_categories_page() {	//Prints out the admin categories page

				include('admin/categories-page.php');	

			}//End function print_admin_categories_page()

			function print_admin_settings_page() {	//Prints out the admin settings page

				include('admin/settings-page.php');	

			}//End function print_admin_settings_page()

	}

  } //End Class local_directory_plugin

	// Instantiate the object
	if (class_exists("local_directory_plugin")) {

		$ld_plugin = new local_directory_plugin();

		} // End instantiation

	//Initialise the admin panel
	if (!function_exists("intialise_admin_panel")) {

		function intialise_admin_panel() {

			global $ld_plugin;

				if (!isset($ld_plugin)) {
					return;
					}

					add_menu_page('Local Directory', 'Directory', 9, basename(__FILE__), array(&$ld_plugin, 'print_admin_summary_page'));
					add_submenu_page(basename(__FILE__), 'Local Directory Categories', 'Categories', 8, 'categories-page' ,array(&$ld_plugin, 'print_admin_categories_page'));
					add_submenu_page(basename(__FILE__), 'Local Directory Settings', 'Settings', 8, 'settings-page' ,array(&$ld_plugin, 'print_admin_settings_page'));

	}	//end local_directory_ap
}	// end admin panel initialisation  

// Set up our hooks

  if (isset($ld_plugin)) {

	  //Actions

		register_activation_hook(basename(__FILE__), 'local_directory_activate');
		register_deactivation_hook(basename(__FILE__), 'local_directory_deactivate');

		add_action('admin_menu', 'intialise_admin_panel');

	  //Filters

	}

?>