How Generate table under database

i made plugin which auto generate database if not exist. same way i want to generate table under generated database. For Example

• I generate database with codes like ABCD
• Now next i want generate DEF table under ABCD database

I try these codes

function plugin_name_activation() {
	require_once( ABSPATH . '/wp-admin/includes/upgrade.php' );
	global $wpdb;
	$db_table_name = $wpdb->prefix . 'table_name';
	if( $wpdb->get_var( "SHOW TABLES LIKE '$db_table_name'" ) != $db_table_name ) {
		if ( ! empty( $wpdb->charset ) )
			$charset_collate = "DEFAULT CHARACTER SET $wpdb->charset";
		if ( ! empty( $wpdb->collate ) )
			$charset_collate .= " COLLATE $wpdb->collate";

		$sql = "CREATE TABLE " . $db_table_name . " (
			<code>id</code> bigint(20) UNSIGNED NOT NULL AUTO_INCREMENT,
			<code>type</code> varchar(100) NOT NULL DEFAULT '',
			<code>extra</code> longtext NOT NULL,
			<code>date_time</code> datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
			PRIMARY KEY (<code>id</code>)
		) $charset_collate;";
		dbDelta( $sql );
	}
}
register_activation_hook(__FILE__, 'plugin_name_activation');

https://web-profile.com.ua/wordpress/dev/create-table-on-plugin-activation/