hbase 分页过滤（新老API的差别）
在hbase2.0以前分页过滤必须以上一次的最后一行+空字节数组作为下一次的起始行，
因为scan扫描的时候是包含起始行的，为了既能准确定位起始行，但又不重复把上一次的最末一行加入下一页，
所以，权威指南里才有了加上空字节数组的处理。
hbase2.0以后，新的api是withStartRow(byte[] startRow, boolean inclusive)，可以直接设置是否包含起始行，完美解决问题，但是又保留了对以前api函数的兼容性。
//分页过滤
private static void pageFilterData() throws IOException{
Table table = helper.getConnection().getTable(TableName.valueOf("testtable"));
final byte[] POSTFIX = new byte[] { 0x00 };
Filter filter = new PageFilter(10); int totalRows = 0;
byte[] lastRow = null;
while(true){
Scan scan = new Scan();
scan.setFilter(filter);
if(lastRow!=null){ //为了兼容以前的scan.setStartRow()代码
//在上一次的最后一行加上一个空的byte数据，在下一个分页上，就会以新的key开始，
// 但是实际上这个key并不存在，所以还是从真正的下一行开始扫描
//这么做的原因是scan的扫描会自动包含起始行，如果不加空字节数据，那么定位上就会把上一次的最后一行作为起始行，最后的数据就会多一行。
//而，新的api是withStartRow(byte[] startRow, boolean inclusive)，可以直接设置是否包含起始行，完美解决问题，但是又保留了对
//以前api函数的兼容性
// byte[] startRow = Bytes.add(lastRow,POSTFIX);
// System.out.println("start row: " + Bytes.toStringBinary(startRow));
// scan.withStartRow(startRow,true); System.out.println("start row: " + Bytes.toStringBinary(lastRow));
//不包含起始行，所以可以直接使用上一次的最后一行作为起始行
scan.withStartRow(lastRow,false);
}
ResultScanner scanner = table.getScanner(scan);
int localRows = 0;
Result result;
while ((result=scanner.next())!=null){
System.out.println(localRows++ + ": " + result);
totalRows++;
lastRow = result.getRow();
}
scanner.close();
if(localRows==0)break;
}
System.out.println("total rows: " + totalRows);
}
兼容老API输出如下：
0: keyvalues={rowKey0/ex:addr/1555078771906/Put/vlen=7/seqid=0, rowKey0/info:username/1555078771906/Put/vlen=5/seqid=0, rowKey0/memo:detail/1555078771906/Put/vlen=7/seqid=0}
1: keyvalues={rowKey1/ex:addr/1555078771906/Put/vlen=7/seqid=0, rowKey1/info:username/1555078771906/Put/vlen=5/seqid=0, rowKey1/memo:detail/1555078771906/Put/vlen=7/seqid=0}
2: keyvalues={rowKey10/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey10/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey10/memo:detail/1555078771906/Put/vlen=8/seqid=0}
3: keyvalues={rowKey11/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey11/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey11/memo:detail/1555078771906/Put/vlen=8/seqid=0}
4: keyvalues={rowKey12/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey12/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey12/memo:detail/1555078771906/Put/vlen=8/seqid=0}
5: keyvalues={rowKey13/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey13/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey13/memo:detail/1555078771906/Put/vlen=8/seqid=0}
6: keyvalues={rowKey14/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey14/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey14/memo:detail/1555078771906/Put/vlen=8/seqid=0}
7: keyvalues={rowKey15/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey15/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey15/memo:detail/1555078771906/Put/vlen=8/seqid=0}
8: keyvalues={rowKey16/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey16/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey16/memo:detail/1555078771906/Put/vlen=8/seqid=0}
9: keyvalues={rowKey17/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey17/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey17/memo:detail/1555078771906/Put/vlen=8/seqid=0}
start row: rowKey17\x00
0: keyvalues={rowKey18/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey18/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey18/memo:detail/1555078771906/Put/vlen=8/seqid=0}
1: keyvalues={rowKey19/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey19/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey19/memo:detail/1555078771906/Put/vlen=8/seqid=0}
2: keyvalues={rowKey2/ex:addr/1555078771906/Put/vlen=7/seqid=0, rowKey2/info:username/1555078771906/Put/vlen=5/seqid=0, rowKey2/memo:detail/1555078771906/Put/vlen=7/seqid=0}
3: keyvalues={rowKey20/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey20/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey20/memo:detail/1555078771906/Put/vlen=8/seqid=0}
4: keyvalues={rowKey21/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey21/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey21/memo:detail/1555078771906/Put/vlen=8/seqid=0}
5: keyvalues={rowKey22/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey22/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey22/memo:detail/1555078771906/Put/vlen=8/seqid=0}
6: keyvalues={rowKey23/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey23/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey23/memo:detail/1555078771906/Put/vlen=8/seqid=0}
7: keyvalues={rowKey24/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey24/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey24/memo:detail/1555078771906/Put/vlen=8/seqid=0}
8: keyvalues={rowKey25/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey25/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey25/memo:detail/1555078771906/Put/vlen=8/seqid=0}
9: keyvalues={rowKey26/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey26/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey26/memo:detail/1555078771906/Put/vlen=8/seqid=0}
start row: rowKey26\x00
0: keyvalues={rowKey27/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey27/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey27/memo:detail/1555078771906/Put/vlen=8/seqid=0}
1: keyvalues={rowKey28/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey28/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey28/memo:detail/1555078771906/Put/vlen=8/seqid=0}
2: keyvalues={rowKey29/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey29/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey29/memo:detail/1555078771906/Put/vlen=8/seqid=0}
3: keyvalues={rowKey3/ex:addr/1555078771906/Put/vlen=7/seqid=0, rowKey3/info:username/1555078771906/Put/vlen=5/seqid=0, rowKey3/memo:detail/1555078771906/Put/vlen=7/seqid=0}
4: keyvalues={rowKey30/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey30/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey30/memo:detail/1555078771906/Put/vlen=8/seqid=0}
5: keyvalues={rowKey31/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey31/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey31/memo:detail/1555078771906/Put/vlen=8/seqid=0}
6: keyvalues={rowKey32/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey32/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey32/memo:detail/1555078771906/Put/vlen=8/seqid=0}
7: keyvalues={rowKey33/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey33/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey33/memo:detail/1555078771906/Put/vlen=8/seqid=0}
8: keyvalues={rowKey34/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey34/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey34/memo:detail/1555078771906/Put/vlen=8/seqid=0}
9: keyvalues={rowKey35/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey35/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey35/memo:detail/1555078771906/Put/vlen=8/seqid=0}
start row: rowKey35\x00
... ...省略其他数据
起始行加了空字节数据，形成了新的定位行（相当于真正的两页之间插入了一个虚拟行用于定位），解决了下一页首行的问题。
新的api输出：下一页的定位行就是上一页的末行，采用新的API设置首行的时候把inclusive设置成false（即不包含首行），那么输出结果就是正确的。
0: keyvalues={rowKey0/ex:addr/1555078771906/Put/vlen=7/seqid=0, rowKey0/info:username/1555078771906/Put/vlen=5/seqid=0, rowKey0/memo:detail/1555078771906/Put/vlen=7/seqid=0}
1: keyvalues={rowKey1/ex:addr/1555078771906/Put/vlen=7/seqid=0, rowKey1/info:username/1555078771906/Put/vlen=5/seqid=0, rowKey1/memo:detail/1555078771906/Put/vlen=7/seqid=0}
2: keyvalues={rowKey10/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey10/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey10/memo:detail/1555078771906/Put/vlen=8/seqid=0}
3: keyvalues={rowKey11/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey11/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey11/memo:detail/1555078771906/Put/vlen=8/seqid=0}
4: keyvalues={rowKey12/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey12/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey12/memo:detail/1555078771906/Put/vlen=8/seqid=0}
5: keyvalues={rowKey13/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey13/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey13/memo:detail/1555078771906/Put/vlen=8/seqid=0}
6: keyvalues={rowKey14/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey14/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey14/memo:detail/1555078771906/Put/vlen=8/seqid=0}
7: keyvalues={rowKey15/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey15/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey15/memo:detail/1555078771906/Put/vlen=8/seqid=0}
8: keyvalues={rowKey16/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey16/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey16/memo:detail/1555078771906/Put/vlen=8/seqid=0}
9: keyvalues={rowKey17/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey17/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey17/memo:detail/1555078771906/Put/vlen=8/seqid=0}
start row: rowKey17
0: keyvalues={rowKey18/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey18/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey18/memo:detail/1555078771906/Put/vlen=8/seqid=0}
1: keyvalues={rowKey19/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey19/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey19/memo:detail/1555078771906/Put/vlen=8/seqid=0}
2: keyvalues={rowKey2/ex:addr/1555078771906/Put/vlen=7/seqid=0, rowKey2/info:username/1555078771906/Put/vlen=5/seqid=0, rowKey2/memo:detail/1555078771906/Put/vlen=7/seqid=0}
3: keyvalues={rowKey20/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey20/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey20/memo:detail/1555078771906/Put/vlen=8/seqid=0}
4: keyvalues={rowKey21/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey21/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey21/memo:detail/1555078771906/Put/vlen=8/seqid=0}
5: keyvalues={rowKey22/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey22/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey22/memo:detail/1555078771906/Put/vlen=8/seqid=0}
6: keyvalues={rowKey23/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey23/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey23/memo:detail/1555078771906/Put/vlen=8/seqid=0}
7: keyvalues={rowKey24/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey24/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey24/memo:detail/1555078771906/Put/vlen=8/seqid=0}
8: keyvalues={rowKey25/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey25/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey25/memo:detail/1555078771906/Put/vlen=8/seqid=0}
9: keyvalues={rowKey26/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey26/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey26/memo:detail/1555078771906/Put/vlen=8/seqid=0}
start row: rowKey26
0: keyvalues={rowKey27/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey27/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey27/memo:detail/1555078771906/Put/vlen=8/seqid=0}
1: keyvalues={rowKey28/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey28/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey28/memo:detail/1555078771906/Put/vlen=8/seqid=0}
2: keyvalues={rowKey29/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey29/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey29/memo:detail/1555078771906/Put/vlen=8/seqid=0}
3: keyvalues={rowKey3/ex:addr/1555078771906/Put/vlen=7/seqid=0, rowKey3/info:username/1555078771906/Put/vlen=5/seqid=0, rowKey3/memo:detail/1555078771906/Put/vlen=7/seqid=0}
4: keyvalues={rowKey30/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey30/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey30/memo:detail/1555078771906/Put/vlen=8/seqid=0}
5: keyvalues={rowKey31/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey31/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey31/memo:detail/1555078771906/Put/vlen=8/seqid=0}
6: keyvalues={rowKey32/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey32/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey32/memo:detail/1555078771906/Put/vlen=8/seqid=0}
7: keyvalues={rowKey33/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey33/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey33/memo:detail/1555078771906/Put/vlen=8/seqid=0}
8: keyvalues={rowKey34/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey34/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey34/memo:detail/1555078771906/Put/vlen=8/seqid=0}
9: keyvalues={rowKey35/ex:addr/1555078771906/Put/vlen=8/seqid=0, rowKey35/info:username/1555078771906/Put/vlen=6/seqid=0, rowKey35/memo:detail/1555078771906/Put/vlen=8/seqid=0}
start row: rowKey35
... ...其他省略
hbase 分页过滤（新老API的差别）的更多相关文章
- Hadoop2.2编程：新旧API的区别
Hadoop最新版本的MapReduce Release 0.20.0的API包括了一个全新的Mapreduce JAVA API,有时候也称为上下文对象. 新的API类型上不兼容以前的API,所以, ...
- Android 新老两代 Camera API 大起底
https://blog.csdn.net/Byeweiyang/article/details/80515192 0.背景简介 最近有一部分相机相关的需求,专注于对拍摄的照片.视频的噪点.色温.明暗 ...
- Java 8的新并行API - 魅力与炫目背后
这是一篇译文,原文链接见这里. 本文同时发表在ImportNew上,转载请注明出处. 我很擅长同时处理多项任务.就算是在写这篇博客的此刻,我仍然在为昨天在聚会上发表了一个让大家都感到诧异的评论而觉得尴 ...
- hbase分页查询
为了广大技术爱好者学习netty,在这里帮新浪微博@nettying宣传下他出版的新书 <netty权威指南>@nettying兄在华为NIO实践多年,这本书是他的技术和经验的一个结晶.N ...
- Hadoop日记Day15---MapReduce新旧api的比较
我使用hadoop的是hadoop1.1.2,而很多公司也在使用hadoop0.2x版本,因此市面上的hadoop资料版本不一,为了扩充自己的知识面,MapReduce的新旧api进行了比较研究. h ...
- hbase分页应用场景及分页思路与代码实现
转自:http://www.aboutyun.com/forum.php?mod=viewthread&tid=7030&extra=page=1 可以带着下面问题来阅读1.hbase ...
- Kafka 0.9 新消费者API
kafka诞生之初,它自带一个基于scala的生产者和消费者客户端.但是慢慢的我们认识到这些API有很多限制.比如,消费者有一个“高级”API支持分组和异常控制,但是不支持很多更复杂的应用场景:它也有 ...
- MapReduce简述、工作流程及新旧API对照
什么是MapReduce? 你想数出一摞牌中有多少张黑桃.直观方式是一张一张检查而且数出有多少张是黑桃. MapReduce方法则是: 1. 给在座的全部玩家中分配这摞牌. 2. 让每一个玩家数自己手 ...
- Hbase 分页设计
hbase 数据获取方式 直接根据 rowkey 查找,速度最快 scan,指定 startrowkey.endrowkey 和 limit获取数据,在 rowkey 设计良好的情况下,效率也不错 全 ...
随机推荐
- HTTP 请求/响应报文结构
请求报文和响应报文都是由以下4部分组成: 1.请求行/响应行 2.请求头/响应头 3.空行 4.消息主体(请求体/响应体) 请求报文结构 请求行 格式为:Method Request-URI HTTP ...
- Bailian 2808 校门外的树（入门线段树）
题目链接:http://bailian.openjudge.cn/practice/2808?lang=en_US 总时间限制: 1000ms 内存限制: 65536kB 描述 某校大门外长度为L的马 ...
- [Unity Shader] 切线空间的法线贴图
切线空间的法线贴图,可以这样理解: #纹理坐标是从0到1,它的坐标是x向右,y向下 #顶点坐标是从-1到-1,坐标是x向右,y向上 1 由表面上某点的切线Tangent.副切线Bitangent.法线 ...
- facebook和twitter的截图分享
记录一下代码,以后自己可以抄..我抄我自己=.= SDK的接入看之前的博客.所以话不多少,直接上代码(记得分享一定要安装原生app(FB和twitter),不然只通过网页分享无法发图片.),初始化都在 ...
- 脚本处理iOS的Crash日志
背景 当我们打包app时,可以选择生成对应的符号表,其保存 16 进制函数地址映射信息,通过给定的函数起始地址和偏移量,可以对应函数具体信息以供分析. 所以我们拿到测试给的闪退日志(.crash)时, ...
- 【Docker】第二篇 Docker镜像管理
一.搜索镜像 1.下载一个docker镜像:我们可以通过登陆docker网站搜索自己需要的镜像,可以选择自己所需要的版本,然后通过详情也可以看到:网址:https://hub.docker.com/2 ...
- ROS (Robot Operating System) 相关资料与文档
本博文持续更新…… ROS学习与实践保护很多资料,最权威的当然是官网: www.ros.org 当然也有很多其他博文,尤其是中文文档有助于理解.2017推出一篇新博文,概况的资料较全. http:// ...
- SQL-Server collation, what is it and how to change db/column collation
The thing about collations is that although database have it's own collation, every table, and every ...
- Performance — 前端性能监控利器
Performance是一个做前端性能监控离不开的API,最好在页面完全加载完成之后再使用,因为很多值必须在页面完全加载之后才能得到.最简单的办法是在window.onload事件中读取各种数据. 大 ...
- nginx模块学习
rewrite模块的语法 链接