BP_Messages_Thread::get_messages_started( int $thread_id )

	public static function get_messages_started( $thread_id ) {
		global $wpdb;

		$bp = buddypress();
		$thread_id = (int) $thread_id;

		$last_deleted_timestamp = static::$last_deleted_message? static::$last_deleted_message->date_sent : '0000-00-00 00:00:00';

		$results = $wpdb->get_col( $sql = $wpdb->prepare(
			"SELECT date_sent FROM {$bp->messages->table_name_messages}
			WHERE thread_id = %d
			AND date_sent > %s
			ORDER BY date_sent ASC, id ASC
			LIMIT 1
		", $thread_id, $last_deleted_timestamp ) );

		return $results[0];
	}