Oracle与Mysql主键、索引及分页的区别,学习oracle的朋友可以参考下
区别:
1、主键,Oracle不可以实现自增,mysql可以实现自增。
oracle新建序列,SEQ_USER_Id.nextval
2、索引:
mysql索引从0开始,Oracle从1开始。
3、分页,
mysql: select * from user order by desc limit n ,m.
表示,从第n条数据开始查找,一共查找m条数据。
Oracle:select * from user
select rownum a * from ((select * from user)a)
select * from (select rownum a.* from (select * from user) a )
where r between n , m .
表示,n表示从第n条数据查询,查找到m条数据。
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