msyql多个or,and,

where (`to`= 2 and `from`= 8) or (`to`= 8 and `from`= 2) and from_unixtime(a.time,'%Y-%m-%d') ='2017-05-31'
order by a.time desc

select a.*,from_unixtime(a.time,'%Y-%m-%d') as t1 from oss_msg as a
where ((`to`= 8 and `from`= 2 ) or (`to`= 2 and `from`= 8 )) and from_unixtime(a.time,'%Y-%m-%d') ='2017-05-31'
order by a.time desc

select a.*,from_unixtime(a.time,'%Y-%m-%d') as t1 from oss_msg as a
where ((`to`= 8 and `from`= 2) or (`to`= 2 and `from`= 8)) and from_unixtime(a.time,'%Y-%m-%d') ='2017-05-31'
order by a.time desc