请试试:
select a.eno, a.tno, a.bdate
from tablename a,(select distinct eno, min(bdate) as bdate from tablename) b
where a.eno = b.eno and a.bdate = b.bdate
select a.eno, a.tno, a.bdate
from tablename a,(select distinct eno, min(bdate) as bdate from tablename) b
where a.eno = b.eno and a.bdate = b.bdate
不过有点复杂,
仔细看看这两个FAQ
http://expert.csdn.net/Expert/FAQ/FAQ_Index.asp?id=78128
http://expert.csdn.net/Expert/FAQ/FAQ_Index.asp?id=6420
另:MySQL目前版本还不支持子查询。
谢谢你的解答,不过你的答案好像没有体现相同eno下bdate最小这个要求
select distinct eno,tno,min(bdate) from table group by eno order by bdate
用select distinct eno,tno,min(bdate) from table
group by eno order by bdate 查得的eno与tno来自不同记录:(
因为MySQL不支持子查询,那有两个办法:
1、建立临时表,效率比下一方法好
2、说明请看MySQL自带的文件
select eno,
substring(min(CONCAT(eno,bdate,tno)),7,10) as bdate,
substring(min(CONCAT(eno,bdate,tno)),17,10) as tno
from table
group by eno