Oracle 分页查询 重复数据的问题
现在一般对Oracle 分页查询实现如下 select * from ( select a.*,rownum r from ( 自己的sql ) a where rownum
现在一般对Oracle 分页查询实现如下
select * from (
select a.*,rownum r from (
自己的sql
) a where rownum ) where r > ?
如果这个sql 按一个含有重复值的字段排序
就会产生在不同页查出重复记录,并且某些记录查不到的现象(不是一定产生)
测试代码如下
CREATE TABLE TEST (
ID VARCHAR2(10) NOT NULL,
OD VARCHAR2(10) NULL
)
GO
--插入测试数据
insert into TEST
select level,case when levelgo
--测试分页结果
第1-5条
select * from (
select a.*,rownum r from (
select t1.id from TEST t1
order by t1.od desc
) a where rownum ) where r > 0
返回结果
行 ID R
1 4 1
2 8 2
3 7 3
4 6 4
5 5 5
第6-10条
select * from (
select a.*,rownum r from (
select t1.id from TEST t1
order by t1.od desc
) a where rownum ) where r > 5
返回结果
行 ID R
1 6 6
2 5 7
3 3 8
4 2 9
5 1 10
可以看到第一个结果集中id=5和id=6 在第二个结果集中也查到了 同时id=9 和id=10的记录都没查到
解决方案如下
如果出现满足上述两个条件的SQL
order by 后再加上表的主键;
如本例中
改为order by t1.od desc,t1.id 后现象消失
如果有更好的解决方法, 希望能告知= =
更多Oracle相关信息见Oracle 专题页面 ?tid=12

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