简单例子:
create table aaaa(
a varchar2(1),
b varchar2(1)
);
insert into aaaa
values('1','a');
insert into aaaa
values('1','b');
insert into aaaa
values('1','c');
insert into aaaa
values('1','d');
insert into aaaa
values('2','a');
insert into aaaa
values('2','b');
insert into aaaa
values('2','c');
结果:
SQL> select a,b,row_number() over(partition by a order by a) from aaaa;
A B ROW_NUMBER()OVER(PARTITIONBYAO
- - ------------------------------
1 a 1
1 b 2
1 c 3
1 d 4
2 a 1
2 b 2
2 c 3