• NoSQL anti pattern – Document Database


    We have a complete scheme for designing relational database schema, but NoSQL does not. Half a year ago, the author read the book “SQL anti mode”, and thought it was very good. Start to pay attention to whether there is anti pattern for NoSQL? Good anti patterns can be found in our design of schema […]

  • Introduction to NoSQL and redis and redis installation and use tutorial under Windows


    NoSQL introduction Before introducing redis, I want to know that NoSQL, or not only SQL, is a kind of non relational data storage, with key / value pair storage. Existing NoSQL DB products: redis / mongodb / memcached / HBase / Cassandra / Tokyo cabinet / Voldemort / Dynomite / riak / CouchDB / hypertable […]

  • People near mongodb implementation


    People near mongodb implementation Recently, Tencent took the product that Zhang Xiaolong was proud of off the shelves. It is just the so-called product: everyone is innocent, and the bottle is innocent, but some people use it to spread pornographic content or advertisements. Therefore, Tencent closed the bottle late on November 30. So as another […]

  • How to avoid access skew and data skew in redis cluster


    [TOC] Summary Most of the redis cluster deployment methods adopt the way of tweemproxy like deployment. That is to say, the redis key is partitioned through the tweetproxy, the redis key is partitioned and allocated to one of multiple redis instances. The structure of the tewmproxy is as follows: Because multiple redis instances behind the […]

  • Events of Alibaba cloud NoSQL database in 2018


    NoSQL first appeared in 1998. In 2009, Johan oskarsson of last.fm launched a discussion on distributed open source database. Eric Evans from Rackspace proposed the concept of NoSQL again. At this time, NoSQL mainly refers to non relational, distributed and does not provide database design mode. From 2009, NoSQL began to rise and develop gradually. […]

  • Comparison between redis and Memcache in NoSQL (1)


    1.Redis(6379) 1) . memory database, default port 6379 2) . data type a) . string (string) b) . hash (structural data) (mostly used when the data has been modified) c) . list [lrange | len | lpop | brpoppush] d) . set [sismember | Sadd] e) . Zset (sorted set ordered set) 3) persistence. a) […]

  • Small program cloud development practice series 02 — cloud database


    I used to use relational database for the first time. I want to share my limited experience with you. I hope it will help developers who are just using NoSQL like me.First of all, let’s talk about the NoSQL integrated in wechat applet cloud development. The official didn’t say what kind of NoSQL database it […]

  • Some concepts of raft protocol


    Some concepts Advantages over other consistency algorithms (Paxos) Simpler, easier to understand Well described Implemented by open source projects and adopted by some companies Security is proven The effectiveness can be compared with other algorithms. The key advantage is still easier to understand. Three states of the server: leader, follower, candidate Leader: processing client requests […]

  • ETCD node failover


    Unreachable member A cluster with etcd containers is created successfully.Check the cluster status with the following command. # etcdctl –endpoint cluster-health If the cluster is running normally, the output looks like: member xxx is healthy: got healthy result from member xxx is healthy: got healthy result from member xxx is healthy: got healthy […]

  • Raft leader election


    Communication: two types of RPC RequestVote RPCs candidates during elections. AppendEntries RPC leaders to replicate log entries and to provide a form of heartbeat. Leader election Raft uses a heartbeat mechanism to trigger the leader election. When servers start, it becomes followers first. As long as the server receives a valid RPCs message from the […]

  • Talk to CTO 〡 and pingcap CTO Huang Dongxu about the new blue ocean of open source database


    Column introduction “Dialogue CTO” is a new column of geek park. It talks about the development and growth of R & D managers from the perspective of technologists. In this column, Wang Yingqi, the founder and CEO of enterprise level R & D management tool one, is invited as an interviewer. Wang Yingqi once participated […]

  • Important concepts and simple usage of elasticsearch


    Then continue to learn the environment built by elasticsearch in the previous article. Starting from the concept, this article will introduce some important concepts and some principled concepts in elasticsearch, hereinafter referred to as es. 1、 Explanation of ES part terms 1. NRT: the full English name is near rrealtime. Near real time, there is […]