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Python linked CSV and MySQL 1, Make sure MySQL is available After MySQL is installed (the simplest installation method is to download the installation package from the official website and then install it step by step), it's time to operate ~ % mysql --version % zsh: command not found: mysql Copy code command not found: mysql appears most ...

Original statement: This article is original by the author (Magic good), which can be used as learning reference reprint, but the source should be indicated. It is forbidden to use it in commercial and other ways without permission, otherwise you will bear the consequences! Preface overview With the increasing complexity of development scen ...

Introduction to xtrabackup As mentioned earlier, the backup method of mysqldump adopts logical backup. Its biggest defect is that the speed of backup and recovery is slow. For a database less than 50G, this speed is acceptable, but if the database is very large, it is not suitable to use mysqldump for backup. At this time, an easy-to-use and ef ...

Summary: 1) mysql query optimization Tables with a large amount of search queries are generally designed as static tables, which exchange space for time     Row of Mysql_ Format - jiangxiaobo - blog Park https://www.cnblogs.com/jiangxiaobo/p/10846694.html #Row of Mysql_ Format (fixed and dynamic)In mysql, if a table does not contain varchar, te ...

Mysql nested subquery Subquery refers to a form of writing in which several small queries with different functions are nested in a complete query statement to complete complex queries together. In order to make readers more aware of the concept of subquery. Results returned by subquery There are four types of data that can be returned by sub ...

1, MySQL trigger 1. Concept of trigger Triggers are database objects related to tables. They can trigger and execute SQL statements defined in triggers before or after insert/update/delete. This feature of trigger can help the application in the database to ensure data integrity, logging, data verification and other operations.The alias ...

I Common database objects objectdescribeTABLEA logical unit that stores data in the form of rows and columnsdata dictionarySystem table, a table that stores database related information. The data of the system table is usually maintained by the database system. Programmers should not modify it, but can only view itCONSTRAINTRules for data veri ...

Demand background Traditional business schemes create relationship tables based on business requirements, but they are aimed at fixed business structures, such as business record ID, creator, creation time, updater, update time, business related fields, etc. to expand fields here, you need to add fields to the corresponding business tables. Ho ...

MySQL is a must for programmers to master. In fact, the language is simple. As long as you practice more, you can master it. 1, MySQL Foundation 1. Database connection tool 1.1 Navicat tutorial Navicat for MySQL tutorial (implementation of addition, deletion, modification and query) 2. DDL operation database SHOW DATABASES; The ...

1, MHA (meaning, composition and characteristics) Meaning (what is MHA) MHA (MasterHigh Availability) is a set of excellent software for failover and master-slave replication in MySQL high availability environment.The emergence of MHA is to solve the problem of MySQL single point.During MySQL failover, MHA can automatically complete the f ...