select t1.id, t1.order_no, t1.order_status, t1.pay_status,t1.shipping_status,
t1.pay_method, t1.invoice, t1.remark, t1.seller, t1.buyer, t1.site_id, t1.order_time, t1.pay_time,
t1.sign_for_time, t1.delivery_time, t1.subtotal, t1.freight, t1.invitation, t1.cope, t1.is_comment,t1.pay_discount from zcwl_order t1 left join
zcwl_order_shipping_address t2 on t2.order_id = t1.id
where t1.site_id order by t1.order_time desc
这条sql语句需要查14秒 如何缩短时间?ps:大概有1w条数据