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Redis教程之代理ip池设计方法详解
前言众所周知代理 ip 因为配置简单而且廉价，经常用来作为反反爬虫的手段，但是稳定性一直是其诟病。筛选出优质的代理 ip 并不简单，即使付费购买的代理 ip 源，卖家也不敢保证 100% 可用；另外代理 ip 的生命周期也无法预知，可能上一秒能用，下一秒就扑街了。基于这些原因，会给使用代理 ip 的爬虫程序带来很多不稳定的因素。要排除代理 ip 的影响，通常的做法是建一个代理 ip...
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redis+mysql+quartz 一种红包发送功能的实现
概要：这篇文章主要是对半年前开发的红包模块进行整理，把其中主要的设计思想以及具体的实现方案进行介绍，如有设计以及实现上的缺陷，或是存在漏洞，请大家批评指正！红包功能大家都很熟悉了，那在这里就简单的对红包功能进行描述......
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Flink Compatibility with Hadoop Comprehensive Tutorial
1. Objective This tutorial on Flink Hadoop compatibility will help you in understanding how Apache Flink is compatible with Big data Hadoop. It will also help you in learning basics of Big Data hadoop...
View ArticlePlatform Update on January 24th
The upcoming platform update is scheduled for January 24th, 2017. ChromeDriver has been updated to version 2.27 . Erlang receives an update with version 19.2 . Firefox ESR has been updated to version...
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Impact of Shared Storage on Apache Cassandra
Every now and then we receive the question of why shared storage isn’t recommended for Apache Cassandra.The conversation usually goes like this: Customer/User “ We have an awesome SAN and would like to...
View ArticleMongoDB ransoms in 2017
You've almost certainly heard the news of the MongoDB ransoms that are going on. It's been a long time coming, and there's no reason for it at all. We learnt a long time ago that it's completely...
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Designing the UFC Moneyball
Using big data analysis on sports? Gigi Sayfan takes us through doing just that with Cassandra/Scylla, mysql, and Redis. In this Compose's Write Stuff article, he shows us how he constructs his own...
View ArticleMongoDB: Basics
Q: How can I see what databases/collections is available? Launch the Mongo DB shell by running mongo (for localhost, or specify some custom host/port along with -u USERNAME -p etc). Once inside the...
View ArticleUsing N1QL Subquery Expressions to Query Over Nested Couchbase Documents
Back in Couchbase 4.0, N1QL was introduced as a way to give developers more flexibility when querying their NoSQL data stored withinCouchbase Server. You could run SQL queries against JSON data and...
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AWS Serverless Lambda Scheduled Events to Store Tweets in Couchbase
This blog has explained a few Serverless concepts with codesamples: Serverless FaaS with AWS Lambda and Java AWS IoT Button, Lambda and Couchbase Microservice using AWS API Gateway, AWS Lambda and...
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流量调整和限流技术
在早期的计算机领域，限流技术(time limiting)被用作控制网络接口收发通信数据的速率。 可以用来优化性能，减少延迟和提高带宽等。 现在在互联网领域，也借鉴了这个概念， 用来为服务控制请求的速率， 如果双十一的限流， 12306的抢票等。 即使在细粒度的软件架构中，也有类似的概念。 两种常用算法 令牌桶( Token Bucket )和漏桶( leaky bucket )是...
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基于 Redis 的代理 ip 池设计
代理 ip 因为配置简单而且廉价，经常用来作为反反爬虫的手段，但是稳定性一直是其诟病。筛选出优质的代理 ip 并不简单，即使付费购买的代理 ip 源，卖家也不敢保证 100% 可用；另外代理 ip 的生命周期也无法预知，可能上一秒能用，下一秒就扑街了。基于这些原因，会给使用代理 ip 的爬虫程序带来很多不稳定的因素。要排除代理 ip 的影响，通常的做法是建一个代理 ip 池，每次请求前来池子取一个...
View ArticleMongo shell：最强大的 MongoDB 管理工具
Mongo shell 是 MongoDB 的命令行管理工具，功能非常强大，最近社区很多人咨询的一些问题，比如 命令行看 json 格式比较吃力？ 如何确定Secondary节点同步是否跟上？ 怎么查看DB、集合使用了多少空间？ 能否在shell 脚本里调用Mongo shell 怎么执行 MongoDB 命令，比如创建集合、索引？ …… 上述问题都可以通过 Mongo shell...
View ArticleRedis---Sorted-Sets数据类型操作
一、概述： Sorted-Sets和Sets类型极为相似，它们都是字符串的集合，都 不允许重复 的成员出现在一个Set中。它们之间的主要差别是Sorted-Sets中的每一个成员都会有 一个分数(score)与之关联 ，Redis正是通过分数来为集合中的成员进行 从小到大的 排序。然而需要额外指出的是，尽管Sorted-Sets中的成员必须是唯一的，但是分数(score)却是可以重复的。...
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Redis---事务
一、概述： 和众多其它数据库一样，Redis作为NoSQL数据库( 不注重表的关系，跟关系型数据库不同 )也同样提供了事务机制。在Redis中， MULTI/EXEC/DISCARD/WATCH 这四个命令是我们实现事务的基石。相信对有关系型数据库开发经验的开发者而言这一概念并不陌生，即便如此，我们还是会简要的列出Redis中事务的实现特征： 1)....
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SMACK stack from the trenches
No Comments This is going to be a sum-up of the experience gathered on various projects done with the SMACK stack. For details about the SMACK stack you might want to take a look at the following blog...
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Tap the power of graph databases with IBM Graph
Natural relationships between data contain a gold mine of insights for business users. Unfortunately, traditional databases have long stored data in ways that break these relationships, hiding what...
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Unstructured Data
Alex Thad hit the ceiling with his current team, in terms of career advancement. He was ready to be promoted to a senior position, but there simply wasn’t room where he was- they were top-heavy as it...
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