select count(1),from as 发消息的人 from A where from!=to group by 发消息的人
select count(*)- (select floor(count(*)/2) from (select * from talk A group by a,b) tmp1,(select * from talk A group by a,b) tmp2 where tmp1.a = tmp2.b and tmp2.a = tmp1.b) from (select count(*) from talk group by a,b) tmp talk 是彪马talk是表名a,b是字段名称
(select floor(count(*)/2) from
(select * from talk A group by a,b) tmp1,(select * from talk A group by a,b) tmp2 where tmp1.a = tmp2.b and tmp2.a = tmp1.b)
from (select count(*) from talk group by a,b) tmp
talk 是彪马talk是表名a,b是字段名称