SQL查詢語句怎樣限定返回結果集的行數？

1、創建測試表，create table test_rows(id number, value varchar(200));

2、插入測試數據，

insert into test_rows

select level, 'val_'||level from dual

connect by level

commit;

3、查詢表中記錄數，總共有999條，

4、編寫SQL，返回最小的10條記錄，

select * from (select t.*, row_number() over(order by id) rn from test_rows t ) where rn=10;