gn name
A 1 ...
A 3 ...
A 2 ...
A 7 ...
B 5 ...
B 4 ...
B 6 ...
选出每组中id最小的记录
A 1 ...
B 4 ...
select * from test as t1 join (select gn,min(name) as n from test where 1 group by gn) as t2 on ( t1.gn=t2.gn and t1.name=t2.n)
A 1 ...
A 3 ...
A 2 ...
A 7 ...
B 5 ...
B 4 ...
B 6 ...
选出每组中id最小的记录
A 1 ...
B 4 ...
select * from test as t1 join (select gn,min(name) as n from test where 1 group by gn) as t2 on ( t1.gn=t2.gn and t1.name=t2.n)