Tag:data model

  • In simple terms vue1.0: Overview

    Time:2021-4-14

    MVVM framework Vue Vue.js The goal of is to implement data binding and composite view component of response through as simple API as possible. Data binding of response (data driven view) As can be seen from the figure,The view on the left (DOM) and the data on the right (common JS object) are bound through […]

  • How to draw charts with JavaScript and HTML5 canvas

    Time:2021-3-31

    Original text:https://code.tutsplus.com/zh-…Original: John negoitaTranslation:Stypstive In this tutorial, I’ll show you how to use JavaScript and canvas to display digital information on pie and doughnut charts. There are actually easier ways to create a chart than from zero to one, such as using theThis chart Library But if you want to know what’s behind the library, […]

  • Distributed basic data model and query language

    Time:2021-3-27

    Most applications are built by stacking data models layer by layer. The key problem for each layer is: how to represent it with the next layer? For example: As an application developer, he observes the real world (including people, organizations, goods, behaviors, capital flows, sensors, etc.) and models them through objects or data structures, as […]

  • The eve of Domain Driven Design: object oriented thinking

    Time:2021-3-9

    object-oriented Object oriented technology is a kind of technology to solve the problemworldUnderstanding and abstract methods. thatobjectWhat is it?Object is the understanding and abstraction of the world, and the world is also called objectcreation. Understanding the world is more complicated, but the world is made up ofthingIt’s made up of.It is such a relationship that […]

  • Data warehouse component: HBase cluster environment construction and application case

    Time:2021-2-19

    Source code:GitHub || GitEE 1、 Introduction to HBase 1. Basic description Hadoop’s native feature is to solve the offline batch processing scenario of large-scale data. HDFS has powerful storage capacity, but it does not provide a strong data query mechanism. HBase component is based on HDFS file system and provides services similar to BigTable. HBase […]

  • Zookeeper data model: characteristics and application of nodes

    Time:2021-2-3

    The basic knowledge of ZK is divided into three modules data model ACL permission control Watch monitoring data model Default profile # The number of milliseconds of each tick tickTime=2000 # The number of ticks that the initial # synchronization phase can take initLimit=10 # The number of ticks that can pass between # sending […]

  • 50 years later, why is SQL still so important?

    Time:2021-2-3

    Translated by: Yuan Yuhan In March 1971, Intel launched the world’s first general-purpose microprocessor, [Intel 4004], which costs $60 and has about 2300 transistors. Today, the latest iPhone has nearly 12 billion transistors and costs just over $60. The changes brought about by 50 years are huge, but some things remain unchanged. In the 1990s, […]

  • CSG construction of solid geometry based on HTML5 canvas

    Time:2021-1-27

    The concept of CSG construction entity geometry has been used by many people in industrial water conservancy and hydropower construction and games. The simplest entity representation is called voxel, which is usually a simple shape object, such as cube, cylinder, prism, pyramid, sphere, cone, etc. According to different packages, these voxels are also different. In […]

  • Play the 3D model of webgl in HTML5

    Time:2021-1-26

    Constructive solid geometry has many practical uses. It is used when simple geometric objects are needed, or where mathematical accuracy is very important. Almost all engineering CAD software packages use CSG (which can be used to represent the features of cutting tools and parts that must fit together). CSG is the abbreviation of constructive solid […]

  • Docker builds Prometheus and grafana to monitor MySQL

    Time:2021-1-8

    Using docker to build MySQL monitoring system [toc] brief introduction Using Prometheus and grafana to build the monitoring system of index collection, storage and display. MySQL is built directly on the host computer. Prometheus and grafana are built through docker. service Start mode Private IP port remarks mysql VM 172.17.0.1 3306 grafana docker 172.17.0.3 3000:3000 […]

  • [Mongo] define schema and flexibly create and read Mongo (zero coding development) (3 / 3)

    Time:2021-1-8

    1. Configuration conf.js module.exports = { db: { url: ‘mongodb://127.0.0.1:27017/local’, options: { useNewUrlParser: true, } } } 2. Entrance index.js const Koa = require(‘koa’); const app = new Koa(); const config = require(‘./conf’) const {loadModel} = require(‘./framework/loader’) //Load the configuration corresponding field of the model loadModel(config)(app) //Introduction of dynamic configuration API const rest = require(‘./framework/router’); […]

  • If only one Python book is recommended, I want to pick it!

    Time:2020-11-19

    In early February of this year, I happened to see a tweet: The author of fluent Python has an exciting message: he’s writing the second edition! If you want to vote for the best Python advanced bibliography, this book will definitely be one of the most popular books. When I first wrote the “Python cat […]