• Rust programming video tutorial (Advanced) — 014refcell and internal variability


    Video address Headline address:https://www.ixigua.com/i677586170644791348…Station B address:https://www.bilibili.com/video/av81202308/ Source address GitHub address:https://github.com/anonymousGiga/learn_rus… Explanation content 1. Internal variability: allows data to be changed when using immutable references. 2. By checking borrowing rules at run time (usually at compile time) by refcell, refcell represents the unique ownership of its data.Similar to RC, refcell can only be used in single […]

  • Solution to the conflict of SQL Server’s sorting rules


    Question:In the development of project database, sometimes the scripts we write have no problem when they are executed locally, but when they are deployed to the server, they are wrong when the scripts run. The Chinese and English error messages are as follows.English: unable to solve the “SQL” problem in equal to operation_ Latin1_ General_ […]

  • 03 nginx lcoation configuration


    1. Location matching command identifier describe = Exact matchingBefore using it in standard URI, the request string and URI should be strictly matched. If the match is successful, stop the match and execute the request in the location immediately. ~ Regular matching; before regular URI, it means that the URI contains regular and case sensitive. […]

  • Install MySQL 8.0 in centos7 (RPM mode)


    Knowledge is everywhere in life, so is work! In the past, I installed MySQL on Linux more than once, which is easy to say. But I wrote an article to summarize and found that there are many details worth learning! Installation package selection Why use RPM? Generally, there are source code compilation and installation, RPM […]

  • Spring cloud (5): Ribbon load balancing mechanism


    1. Test custom load balancing rules 1.1 server To create a first boot project: pom: 4.0.0 org.crazyi.cloud first-boot 0.0.1-SNAPSHOT org.springframework.boot spring-boot-starter-web 1.5.7.RELEASE Person: package org.crazyit.cloud; public class Person { private Integer id; private String name; private Integer age; private String message; public Integer getId() { return id; } public void setId(Integer id) { this.id = […]

  • Daily question – Flip by column to get the maximum number of equal rows


    Given a matrix consisting of several zeros and ones, select any number of columns from the matrix and flip each cell on it. After flipping, the value of the cell changes from 0 to 1, or from 1 to 0. Returns the maximum number of rows on which all values are equal after some flipping. […]

  • Yixin’s 105 database rules


    Abstract: This paper introduces the 105 database military regulations of Yixin, which helps the R & D team to evaluate the quality of database development and achieve the goal of finding and solving problems as soon as possible. As a financial technology enterprise, a large number of businesses of Yixin rely on databases. How to […]

  • Using tcpkill to kill TCP connection


    In the process of using long connection, if some long connection is always connected, you can use tcpkill command to kill this connection Install tcpkill. Tcpkill uses a small tool of dsniff apt install dsniff   Use process: For example, the connection to the 8082 port of the server     Kill the connection. The […]

  • K8s actual combat (11) | service: progress of service


    preface Ingress can be understood as the service of service, that is to build a service layer in front of the existing service, as the unified entrance of external traffic, to forward the request routing. To put it bluntly, it is to build a nginx or haproxy on the front end, forward different hosts or […]

  • On SQL parsing, why is the programming language parser ANTLR better?


    This article is reproduced from: dbaplus community Introduction to the author Du Hongjun,Software Engineer of Jingdong Digital Technology Co., Ltd., with many years of middleware development and system design experience, has in-depth understanding of spring, mybatis and other related open source technologies. At present, I am responsible for the development of SQL parsing in the […]

  • [JS design pattern]: strategy pattern and application – Implementation of bonus calculation and form verification (5)


    introduce The meaning of strategy pattern is to define a series of algorithms, encapsulate them one by one, and make them replaceable. This mode allows algorithm changes not to affect customers who use the algorithm. realization For example, data validity verification is usually implemented by swich or if statement. If there are too many verification […]

  • Freight template of e-commerce system design (2)


    E-commerce people use it every day, such as a cat, a dog, etc.The design of e-commerce system seems complex and simple, and it seems simple and complexThis chapter is suitable for junior and intermediate engineers to have a close look. Please feel free to do so preface In the order system, the freight template is […]