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数据引擎查询原理及应用
极牛技术实践分享活动 极牛技术实践分享系列活动是极牛联合顶级VC、技术专家，为企业、技术人提供的一种系统的线上技术分享活动。 每期不同的技术主题，和行业专家深度探讨，专注解决技术实践难点，推动技术创新，每周三20点正式开课。欢迎各个机构、企业、行业专家、技术人报名参加。 嘉宾介绍...
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hbase常用命令
1. 概览 HBASE常用shell命令如下： 名称 命令表达式 创建表 create '表名称', '列名称1','列名称2','列名称N' 添加记录 put '表名称', '行名称', '列名称:', '值' 查看记录 get '表名称', '行名称' 查看表中的记录总数 count '表名称' 删除记录 delete '表名' ,'行名称' , '列名称' 删除一张表...
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MongoDB在58同城百亿量级数据下的应用实践
本文转载自极客邦培训（微信号： gittraining）。 58同城作为中国最大的生活服务平台，涵盖了房产、招聘、二手、二手车、黄页等核心业务。58同城发展之初，大规模使用关系型数据库（SQL Server、mysql等），随着业务扩展速度增加，数据量和并发量演变的越来越有挑战，此阶段58的数据存储架构也需要相应的调整以更好的满足业务快速发展的需求。...
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ClusterControl 1.3.2 发布，数据库集群控制
ClusterControl 1.3.2 发布了，ClusterControl 是一个数据库的集群控制程序，支持 mysql 和 PostgreSQL 。包括： 支持 MySQL 5.6 和 Galera 3.x builds 支持 AWS VPC (Beta) 用户自定义报警和提醒 支持无代理监控 本次发布，一些提升： For MongoDB Deploy or add existing...
View Article网络分区引发的 oplog 乱序问题
OplogOutOfOrder problem 线上一个Secondary节点crash，错误原因是出现了 OplogOutOfOrder 错误，也就是说Secondary 重放了一条比『已经重放过最新的 oplog』更早的操作，经过分析，发现问题是因网络分区导致出现2个 Primary 的问题导致，详细的过程如下表分析。...
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关于MongoDB Sharding，你应该知道的
MongoDB Sharded Cluster 原理 如果你还不了解 MongoDB Sharded cluster，可以先看文档认识一下 中文简介： MongoDB Sharded cluster架构原理 英文汇总： https://docs.mongodb.com/manual/sharding/ 什么时候考虑用 Sharded cluster？ 当你考虑使用 Sharded cluster...
View Article[Hadoop] 关于Hadoop的NetworkTopology的遇到的一些问题
背景问题 问题是周末，其他团队HBase推数据变慢了，我也跟着一起找问题，现象是新加的节点的网络流量非常大，后来帮哥发现是原来没有配机架的集群，新机器配了机架，既然加了机架导致这个问题，那我们把机架变为没变机架的时候，是否就可以解决这个问题？后来发现已经加的节点无法从已经加入的机架去除，这就要找根本的问题了。 问题：为什么我更新原有DN的机架信息不生效？ 关于机架...
View ArticleHadoop Weekly Issue #185
05 September 2016 This is a short and sweet issue covering Facebook's usage of Spark, a comparison between Apache Flink and Apache Kafka Streams, new releases of Apache Ambari and Hortonworks Data...
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开学好成绩！新华三获Hadoop/Spark大数据认证6项第一
通信世界网消息(CWW) 开学季来到，新华三集团迎来新学期首轮好成绩：以12项测试6项第一的傲人成绩，通过大数据Hadoop/Spark产品能力认证性能专项测试，并在9月1日2016可信云大会开幕式中获颁证书，成为新华三大数据平台继4月25号基础能力认证之后的又一突破。这标志着新华三在大数据领域领先的技术实力受到业界的一致认可，也预示着新华三在大数据道路上又往前迈进了一大步。...
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Classic WTF: The Big Ball of Yarn
It's Labor Day in the US, so we're taking the day off to grill something before the weather turns horrid. While I was finding legacy articles to support the Your Code Might Be Unmaintainable… article,...
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Review: Google Bigtable scales with ease
When Google announced a beta test of Cloud Bigtable in May 2015, the new database as a service drew lots of interest from people who had been using HBase or Cassandra. This was not surprising. Now that...
View ArticleThe Mongoid Community Organization
You may have seen my Getting Things Done with Mongoid series of posts. Over the past few weeks I’ve been helping out a bit with creating a home for the many mongoid-* Ruby projects. You might want to...
View Articlecassandra没法使用jps等工具
安装好cassandra之后，用jps发现没有cassandra服务进程。而netstat和ps显示进程和端口都已经启动。 google找到几篇相关的文章： [1] CASSANDRA-9483 [2] jps-or-jstat-unable-to-monitor-DSE-processes/cassandra [3] jvmoption-2.html...
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Miles to go ... - Arun Gupta: Docker Service and Swarm Mode to Create...
Docker 1.12 introduced Services .A replicated, distributed and load balanced service can be easily created using docker service create command. A “desired state” of the application, such as run 3...
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My Neo4j Summer Road Trip to the World of Healthcare [Part 4]
ByYaqi Shi, Developer Relations | September 7, 2016 Part 4: Create Relationships with FuzzyWuzzy Welcome back to my adventure to the world of healthcare! In the past three blog posts, I have discussed...
View ArticleDBA Days: Chaos Sloth
I love a bad idea I mean, just look at me. I’m covered in them! So when Brent wanted to randomly make his server act crappy, I wrote a script for it. Usual caveats here. Don’t run this in production....
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Considering Alternatives To RDBMS? NoSQL May Be The Answer
In today’s digital economy,big data, mobile and IoT are pushing the limits of traditional RDBMS capabilities. While the growth of available data is staggering, businesses struggle to take full...
View ArticleNDP Episode #9: Graph Databases with Neo4j
I am pleased to announce that the ninth episode of the NoSQL Database Podcast has been published to all the popular podcast networks. In this episode titled, Graphing Databases with Neo4j , I am...
View ArticleNoSQL Biggest Lie: SQL Never Went Away
NoSQL databases threw out SQL for querying, while their authors focused on solving problems on scale, speed and availability. The trouble is, the need for rich query never went away. Neither did SQL;...
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