private function has_user_earned() {

		global $wpdb;

		$count = (int) $wpdb->get_var(
			$wpdb->prepare(
				"
			SELECT COUNT( pm.meta_id )
			FROM {$wpdb->postmeta} AS pm
			JOIN {$wpdb->prefix}lifterlms_user_postmeta AS upm ON pm.post_id = upm.meta_value
			WHERE pm.meta_key = '_llms_achievement_template'
			  AND pm.meta_value = %d
			  AND upm.meta_key = '_achievement_earned'
			  AND upm.user_id = %d
			  AND upm.post_id = %d
			  LIMIT 1
			;",
				array( $this->achievement_template_id, $this->userid, $this->lesson_id )
			)
		);

		/**
		 * @filter llms_achievement_has_user_earned
		 * Allow 3rd parties to override default dupcheck functionality for achievements
		 */
		return apply_filters( 'llms_achievement_has_user_earned', ( $count >= 1 ), $this );

	}