• Elasticsearch multiple search methods


    The previous chapter mainly introduces some important concepts and simple crud of ES, and this chapter will focus on multiple query methods of ES. In the process of using ES, query is the most important application scenario. 1、 Query string search 1. Search all products GET /shop_index/productInfo/_search Return result: { “took”: 8, “timed_out”: false, “_shards”: […]

  • Installing HBase in Linux


    Environmental requirements:1. Linux system2.jdksetup script1. Download and unzip the installation file  wget http://mirror.bit.edu.cn/apac…  tar xvfz hbase-0.94.16.tar.gz 2. Start HBase  /usr/hbase-0.94.16/bin/start-hbase.sh If you make a mistake+======================================================================+       Error: JAVA_HOME is not set and Java could not be found         Please download the latest Sun JDK from the Sun Java web site               > http://java.sun.com/javase/do… <                                                                                            Hadoop […]

  • There are tens of decimal places after two tables are associated in Clickhouse


    problem During a Clickhouse data query, QA reported that there were dozens of decimal places in some index data in the list. I thought it was a bug in dataformat Resulting in. So start from the interface and follow the data all the way to the data source. It is found that the decimal point […]

  • Tencent heavy open source distributed NoSQL storage system DCache


    When you kill commodities on the e-commerce platform or brush hot topics on the social network, you can clearly feel the horror of the current network data flow. Hundreds of thousands of commodities are sold out within a second after they are started; the number of instant reading and forwarding can reach hundreds of millions […]

  • Message system architecture in modern IM system


    Preface The full name of IM is instant messaging, and the Chinese name is instant messaging. In this highly information age of mobile Internet, Im products have become necessary products in our life, such as nailing, wechat, QQ and other products with IM as the core function. Of course, wechat has grown into an ecological […]

  • Insight into the database frontier, gathering the best lineup of Alibaba cloud database, DTCC 2019, top eight highlights


    Abstract:As an old friend of DTCC and the world’s leading cloud computing manufacturer, Alibaba cloud database team is invited to participate in this technology event. It will not only send a team of distinguished guests, but also present 8 wonderful topics for the vast number of database industry professionals and users. The following editor combed […]

  • Message system architecture model in modern IM system


    Preface In the architecture part, we introduce the architecture of modern IM message system, the abstract model of Timeline and the typical architecture of a message system based on the Timeline model, which supports multiple advanced functions of “message roaming”, “multi terminal synchronization” and “message retrieval”. In order to simplify the reader’s understanding of the […]

  • Pymongo basic operation instruction


    1. Create a connection import pymongo Conn = pymongo. Mongoclient (‘localhost ‘, 27017) 񖓿 after the installation and start of the service, the default local connection Conn = pymongo. Mongoclient() defaults to the above address and port Conn = pymongo. Mongoclient() 񖓿 connect to the database DB = conn [‘like’u name ‘] (get database with […]

  • Share the evolution of fusion of didi distributed NoSQL database


    Product dribble TechnologyBy Yu Wenlong Fusion is a distributed NoSQL database developed by Didi. It is fully compatible with redis protocol and supports large-scale data persistence and high-performance reading and writing. It supports hundreds of businesses in Didi, with Pb level data storage, and is one of the most widely used primary storage services. In […]

  • Model name details of mongodb


    Recently, I studied the API design and mongodb by the way. I didn’t read the tutorial carefully, so I also encountered some strange phenomena in the use process. For example, I found that the name of the model I created is inconsistent in the corresponding database collections. I wonder, for example, what I created is […]

  • Bigdata NoSQL — overview of apsaradb HBase data storage and analysis platform


    I. Introduction By 2019, the database has reached a new turning point, with three obvious trends: More and more databases will be cloud native, and will constantly make use of new hardware and advantages of cloud itself to build cloudnative databases. In China, Alibaba cloud’s cloud HBase and polardb are the representatives. This article will […]

  • A summary of mongodb in NoSQL


    NoSQL has been popular for a long time, so in what scenarios do you need to use these “emerging things”, such as mongodb? Here are some summary: You expect a higher write load By default, mongodb pays more attention to high insertion speed than transaction security. If you need to load a large amount of […]