Why I’m excited about Yarn
Today, Facebook in collaboration with Google and others released Yarn, a new package manager for javascript: The Yarn website lists a few benefits such as speed, reliability, and security (amongst...
View ArticleEnabling Enterprise Apps & Simplify Transition from RDBMS
Couchbase is all about enabling more and more enterprise applications to leverage and adopt NoSQL/JSON data model. N1QL simplifies this transition from traditional Relational databases, and is built...
View ArticleRavenDB Retrospective: BASE Indexes
RavenDB was designed from the get go with ACID documents store, and BASE indexes. ACID stands for Atomic, Consistent, Isolated, Durable, and BASE stands for Basically Available, Soft state, Eventually...
View ArticleTesting yarn, a fast npm for JavaScript
TL;DR: It’s crazy fast and you should get it asap Hello, Today, a group of engineers from Facebook, Google, Exponentjs and Tilde released a new tool called yarn . It’s a new tool aiming to replace npm...
View ArticleCassandra with Spark 2.0 : Building Rest API !
In this tutorial , we will be demonstrating how to make a REST service in Spark using Akka- http as a side-kick ;) and Cassandra as the data store. We have seen the power of Spark earlier and when it...
View Article关于用redis实现动态时间段内统计排序的想法
问题描述 需要根据某类数据在动态时间段内的统计值对这些数据进行排名。例如按过去24小时内点赞数排名的帖子,每隔一小时计算一次结果。以下描述均针对这个例子展开。 解决思路 针对这种问题,我的第一反应是直接通过 mysql 一张数据表记录所有数据的每一条统计值改变的行为,例如记下每个帖子在哪个时间点被谁点赞。排序结果直接通过 select + where + order_by + limit...
View ArticleOn the Phone with an Attivio BDR
As a business development representative at Attivio, I regularly speak to companies about their big data management challenges and possible technology solutions. Many of their pain points would...
View Article【Problems】Cloudera Manager错误集锦
本博客文章如无特别说明,均为原创!转载请注明出处:Big data enthusiast( http://www.lubinsu.com/ ) 本文链接地址: 【Problems】Cloudera Manager错误集锦 ( http://www.lubinsu.com/cloudera-manager-errors/ ) 问题描述: 文件系统检查点已有 1 天,14 小时,36...
View Article[原]优化文件下载性能,缓存MongoDB GRIDFS文件(实践讨论稿)
当前的多机集群系统中,文件(附件)的上传、下载服务是通过网络文件系统(NFS),在NFS的应用中,本地NFS的客户端应用可以透明地读写位于远端NFS服务器上的文件,就像访问本地文件一样,以此形成集成负载均衡方式环境下的共享盘功能,如下图所示。 在系统中,文件管理使用MongoDB...
View ArticleGriffin―Model-driven Data Quality Service on Cloud for Both Real-time and...
Overview of Griffin At eBay, when people use big data (Hadoop or other streaming systems), measurement of data quality is a significant challenge. Different teams have built customized tools to detect...
View Article【译】Facebook发布了新的Node模块管理器Yarn,或将取代 npm 客户端
在 javascript 社区中,工程师们互相分享成千上万的代码,帮助我们节省大量编写基础组件、类库或框架的时间。每个代码包可能都依赖于其他代码,而代码间的依赖关系则由包管理器负责维护。目前最流行的 JavaScript 包管理器是 npm 客户端,在 npm 仓库中提供了多达 30 万的软件包。据统计,已有超过 500 万的工程师使用 npm 仓库,其软件包下载量达到了 50 亿次/月。 在...
View ArticleAmazon ElastiCache for Redis Update Sharded Clusters, Engine Improvements, an...
Many AWS customers useAmazon ElastiCache to implement a fast, in-memory data store for their applications. Welaunched Amazon ElastiCache for Redis in 2013 and have added snapshot exports to S3 ,...
View Article百万级消息推送 Redis 性能排查
百万级消息推送 Redis 性能排查 You are here:架构&实践 -性能和可伸缩性 Frank2015/02/22阅读: 503评论: 0收藏: 0 服务性能 Redis 最近查看消息推送的监控信息,日推送量到百万,但是随之而来的是 TP99 搞到 5秒,详细对日志打了埋点,监控其瓶颈,最终定位是 Redis 的性能问题。但是令人疑惑的是,对比了其他应用系统 Redis...
View ArticleCassandra源码分析-Network
Cassandra-2.2 源码分析:Netty客户端/服务端、请求处理、消息服务 CassandraDaemon 启动日志,代表了各个组件的启动顺序 INFO [main] 2016-10-11 15:39:47,410 ColumnFamilyStore.java:382 - Initializing system.sstable_activityINFO [main] 2016-10-11...
View ArticleTOP4 - TP5数据库
准备5.0的数据查询由低到高分三个层次:数据库原生查询(SQL查询);数据库链式查询(查询构造器);模型的对象化查询;本章会涉及到前面两个,模型的查询会在第六章进行讲解。 在第一章已经提到,在使用Db类进行数据库查询之前,首先必须先创建一个控制器类,以及一个操作方法用于测试,类似于:...
View Article11gRAC搭建单机Dataguard
本实验是oracle 11.2.0.4 RAC 对单机本地文件路径的DataGuard 推荐设置/etc/hosts文件的域名解析,方便后面的配置,因为IP非常容易乱套了我的是直接将所有的节点(包括备机)的etc都设置成完全的,一样的, 192.168.115.100 rac1 192.168.115.101 rac2 192.168.115.110 rac1-vip 192.168.115.111...
View ArticleSQL查询数据库中所有表中的字段名和字段类型
这里总结几个数据库的查询所有表字段名和字段类型的SQL语句: mysql database: select COLUMN_NAME, DATA_TYPE from information_schema.COLUMNS where table_name = Oracle database: select column_name, data_type from all_tab_columns where...
View ArticleSqlite3瞎捣鼓笔记
目录目录 Sqlite3 数据库SELECT INSERT UPDATE Sqlite3 数据库UPDATE OF 触发器INSERT 触发器 Sqlite3 sum函数求某记录的比例 Sqlite3 substr字符串截取函数获取未知长度的前n-1个字符 Sqlite3 创建内存数据库 Sqlite3 导出内存数据库到文件...
View ArticleOracle数据库(十)PLSQL
--打开输出开关set serveroutput on--PLSQL语法格式declare --说明部分begin --程序 dbms_output.put_line('Hello World');end;/--if 语句--判断用户从键盘上输入的数字set serveroutput on--接收键盘输入 --num: 地址值,在地址上保存了输入的数字accept num prompt...
View Article2PL/SQLLanguageFundamentals(基本原理)
This chapter explains these aspects(方面) of the PL/SQL language:■ Character Sets■ Lexical Units(词法单元)■ Declarations■ References to Identifiers(引用标识符)■ Scope and Visibility of Identifiers(标识符的范围和可见性)■...
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