MySQL

Description: This script is tested for data cleansing, cleaning up a single table, cleaning up problems, and can be rolled back for single-table recovery.Scripting Features:Script 1 for single-table backupsScript 2 for data recovery of a single

--01 MySQL database operation--Link Database- -Pmysql--No password displayed- - Pmysql--Exit the databaseQuit/exit/+ D--The SQL statement needs a semicolon at the end;--Show Database version versionsSelect version ();--Show timeSelect Now ();--View

SQL Statement Combat-DML Statement (emphasis) Select: SELECT * FROM table1 where range Insert: INSERT INTO table1(filed1,filed2)values (filed1,filed2) Explanation:filed1,filed2 field name ; filed1,filed2 field valueDelete: Delete from table1 where

Xtrabackup is a free database hot-backup software Percona open source, which can back up non-blocking databases of InnoDB and XTRADB storage engines (as well as a table lock for MyISAM backups).In contrast to mysqldump backup, mysqldump is a logical

MySQL Import SQL fileSOURCE D:/dbname.sqlCreate a MySQL database and set the encodingCREATE DATABASE procedure_function DEFAULT CHARACTER SET UTF8 COLLATE utf8_general_ci;Create a databaseCREATE database name;2. Import the databaseMethod One:(1)

Common policies for query optimization1. Optimize data access: Applications should reduce data access to the database and the database should reduce the number of records actually scannedFor example, Redis cache, avoid "select * FROM table"2.

Download Open source MySQL, depending on the version of the selected responsehttps://dev.mysql.com/downloads/mysql/InstallationIf you encounter the following errorInstallation Error MSVCP120.dll and MSVCR120.dllinstallation

Master-slave replication consists of two steps:The settings on the Master Master server (group), and the settings on the slave subordinate server (group).Environment:Master:192.168.155.101slave:192.168.155.102Note the point:1. Configure the master

internal coupling:(1) The standard junction does not establish a junction condition (where statement), because the number of results returned is the number of rows in the first table x the rows in the second table, and this phenomenon is called

Left join returns records that include all the records in the left table and the equivalent of the junction fields in the right tableRight join returns records that include all records in the right table and the junction fields in the left

It was suggested that 4 sheets be merged into one. The data volume is large, there are 40 million data. There is a lot of duplication of data that requires a column to be de-weighed.Ideas:1, export data. SELECT INTO outfile.2. Transfer to the server

Database access Here's an ORM framework for node sequelize to operate the database, for example MySQL.To configure database connection information config/db_config.js:1 // Db_config.js 2 module.exports = {3 database: ' H_api ',// library

Currently the most popular database:Oracle, MySQL, SQL Server, DB2, Sqline--: Single line comment#: Also single-line comment/* Comment Content */: Multi-line CommentMysql-uroot-p Password: Log in to MySQLService mysqld RestartRestart

This address: http://www.cnblogs.com/jying/p/8877065.htmlrequirement: Get the date of 15th last month Web Search a large pile of paste copy of The Big Pit: (The following is the last day of the search last month, but I do not necessarily what day

1, MySQL Foundation and SQL statement CombatMySQL is a relational database management system, which is very popular in internet companies.Install with the Yum command under LinuxReal: Connect database 172.16.41.89Log in to MySQL command:Mysql-u root-

MySQL Client/server ProtocolIt is accurate to say that the MySQL Client/server protocol, another called X protocol is not involved. The address is as follows: MySQL client/server Protocolbyte orderThe byte order in the general Agreement refers to

The content of this article: MySQL Learning route Starting Date: 2018-04-19 Since many of these are APIs now, many of them have been transferred to the programming language, so this MySQL path is just for "understanding". Don't delve

Purpose of the projectMigrating data from MySQL 5.5.53 built with Phpstudy in the original Windows environment to a new host Linux environmentEnvironmental situation新主机系统平台：CentOS release 7.4 (Final) 内核

OK, nonsense not much to say, on dry goods.Tuning ideas:? 0. Hardware optimization? 1. Database design and planning-it's cumbersome to revise later, estimate the amount of data, use what storage engine? 2. Application of data--how to fetch data,

The role of the MySQL foreign key:Maintain data consistency, integrity, the primary purpose is to control the data stored in the Foreign key table. Make two tables associative, and foreign keys can only refer to the values of columns in the