SELECT * FROM `t_order` WHERE ( `order_userid` = 110000 ) AND ( `order_status` = 2 ) AND ( order_time >= 1489161600 and ( order_playtype = "offline" or order_playtype = "balance" or (order_playtype = "online" and order_playstatus = 2)) ) ORDER BY order_id desc LIMIT 30,15

where条件要满足以上，请问各位大神怎么优化啊，现在一查询要1000多秒，几乎是全表扫描了。