MySQL:
limit
select * from tableName limit 3 默认从第0条开始取3条
select * from tableName limit 3,3 从第3条开始(不包括第3),取3条数据
Oracle
子查询rownum
select t1.*
from
(
select rownum rnum,*
tableName
where
rownum <= 20
) t1
where t1.rnum > = 10