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Step 1: - Preparation-- Create (projiect) folderOpen the terminal under the current file -- enter a command -- create a package management file npm i npm init -y or npm init // Generate package.json source file; If the name of the project folder is in Chinese, use npm init. If it is in English, use npm init directly npm init -y npm i my ...

In the early stage of application development, the amount of data is small. When developing functions, the program pays more attention to the realization of functions. With the growth of production data, many SQL statements begin to expose performance problems and have a greater and greater impact on production. Sometimes these problematic SQL ...

mysql installation Uninstall the original mysql #Check whether there is a built-in mariadb rpm -qa | grep -i mariadb #If yes, uninstall the built-in mariadb rpm -e --nodeps mariadb-libs Modify / tmp directory permissions chmod -R 777 /tmp Check for dependencies #The current package should exist [there are many virtual machines under no ...

🍅 Author home page: Li Yangyong   🍅 Introduction: high quality creator in Java field 🏆, [Li Yangyong] author of public account ✌   Resume template, learning materials, interview question bank [pay attention to me and give it to you] 🍅 Get the source code at the end of the article 🍅   Near the end of the semester ...

Use the SELECT statement for basic queries in the studentsdb database. (1) In the student_info table, query each student's school number, name, birth date information. SELECT School Number,Full name,Date of birth FROM `student_info`; (2) Query the names and home addresses of students whose student_info form number is 0002. SELECT Full name ...

1, Column attribute problem auto_ The increment dimension must be a primary key When creating a table, once you use auto_ For the increment description field, after a single piece of data corresponding to the primary key field is deleted, no data can be added to the corresponding content of this primary key field. As shown in the following f ...

Twenty thousand words. The blogger worked hard to write it for you. I'm here for three consecutive ~ ~. 1, Introduction to JDBC That is, Java Database Connectivity, Java and database links. Is an API that can execute SQL statements. JDBC is a specification, which provides a complete set of interfaces, allowing portable access to the unde ...

catalogue Environment construction database Create Maven project Configuration item Write project Create package structure Writing back-end code pojo package util package   service package serviceimpl package controller package Create front-end display page Possible problems Tomcat startup failed. Garbled code problem We ...

2, MySQL Cluster Construction 2.1 cluster requirements Build a master-N-slave MySQL Cluster;The slave node can be expanded horizontally;All write operations can only be performed on the Master node;All read operations can be performed on all nodes; 2.2 build clusters in physical machine environment Next, let's look at a schematic diagram of ...

JDBC core knowledge points 1. What is JDBC? JDBC is a set of specifications proposed by SUN company, which provides unified access to a variety of relational databases. 2. What are the components of JDBC? JDBC is composed of a set of interfaces proposed by SUN company and implementation classes (driver jars) provided by various database man ...