字段1     字段2      ……  
   id        name      
   1           a      
   2           b 
   3           c 
   4           c 
   5           b 
   6           ……

select id,name
from (
select id,name,row_number(partition by 分组键 order by 排序键) rn
) where rn=1;

------解决方案--------------------
SQL code

--假设table为t
--第一个sql
select * from t where rowid in
(select max(rowid) from t group by t.name)
order by id;
--第二个sql
select id,t.name,t2.cou
from t,(select name,count(name) cou
from t group by name
) t2
where t.name=t2.name
order by t.id;

------解决方案--------------------
SQL code
order by t2.cou;

------解决方案--------------------

探讨


第一sql

SQL code
select id,name
from (
select id,name,row_number(partition by 分组键 order by 排序键) rn
) where rn=1;