MySQL

Installation of Linux version (too simple)Installation:? 1 yum install mysql-server　　 Service-side startup? 1 mysql.server start Client connections? 1234567

MySQL data type Integral type Key words Length TINYINT 1Byte SMALLINT 2Byte Mediumint 3Byte INT | INTEGER 4Byte

Today's production environment MySQL encountered a problem, an application in the production environment is a distinction between uppercase, but MySQL is not case-insensitive, this is the pit dad, the data found to have two, the program error said

View MySQL Error tips170329 ,: -: atMysqld_safe number of processes running now:0170329 ,: -: atMysqld_safe mysqld restarted170329 8: -: at[Note]/usr/local/mysql/bin/mysqld (mysqld5.5. --log) starting asProcess4353 ...170329 8: -: at[Note]

Recently, due to the need for work, we began to focus on the relative optimization of select query statements for MySQL databases.Because of the actual project involved, it is found that when the data volume of MySQL table reaches millions, the

Under Window1. Export the entire databaseMysqldump-u user name-p database name > exported file nameMysqldump-u dbuser-p dbname > Dbname.sql2. Export a tableMysqldump-u user name-P database name Table name > exported file nameMysqldump-u dbuser-p

MySQL Add, delete, check, change operation command:First, modify MySQL Database passwordFormat: Mysqladmin-u username-P Old password password new password.Second, viewSee how many databases: Notice the back with S#查看SHOW DATABASES;#查看表USE blog; SHOW

Introduction: MySQL Join connection, summed up under a total of the following several common ways, with a picture more intuitive to display:1.inner join: That is, the portion of B in the query graph, which is the data shared by both A and B tables,

Environment Preparation:Deploy a master one from two servers, achieve master-slave replication, the main library to open Binlog, the main library and the Server-id from the library to be differentMain Library:[Email protected] ~]# hostname-i10.0.0.51

Requirements Description:Case background: In the course of bank transfer, accidents are unavoidable. To avoid unnecessary losses caused by an accident, the transaction is handled in the same way:A account has an existing balance of $1000 and a

MySQL's master-slave is an asynchronous replication process, which is actually a process of copying data from the master to the slave end. The entire replication process between Master and Slave is performed primarily by three threads, of which two

A subquery is the nesting of another query statement in a query statement.The query part outside the subquery is referred to as an external query.The subquery must contain parentheses.Any, in, someThe Any keyword must be used with a comparison

#mysql basic Commands#1, view all databases#show databases;#2, creating a database#create database dbname;#3, using the database#use dbname;#4, view the tables in the library#show tables;#5, creating data tables#filid int PRIMARY Key

The steps are as follows:1. Modify Master server Master:#vi/etc/my.cnf[Mysqld]Log-bin=MySQL-bin//[must] enable binary loggingserver-id=222//[must] server unique ID, default is 1, usually take IP last paragraph2. Modify the slave from the

MySQL allows remote access1. Initialize root passwordGo to MySQL DatabaseMysql>update user Set Password=password (' 123456 ') where user= ' root ';2, allow MySQL remote access, you can use the following three ways:(1) Change the table.Mysql-u

Convert date format to int using Unix_timestamp ()For example:Select Now (), Unix_timestamp (now ());Now () | Unix_timestamp (now ())2014-11-28 09:54:43 | 1417139683Use From_unixtime () to convert a date from an int type timestampFor example:Select

1. Preparation of installation Environment# Wget-o/etc/yum.repos.d/centos-base.repo Http://mirrors.aliyun.com/repo/Centos-6.repo# yum Install cmake-y# yum install ncurses-devel-y# useradd-s/sbin/nologin-m MySQL2, the compilation environment

1. Using the mysqldump commandBackup: Mysqldump-u username-p dbname table1 table2 ...> backupname.sqlRestore: Mysql-u username-p [dbname]Mysqldump-u root-p123456MySQL user servers> Backup.sql//put the library under MySQL table user, table servers

Explain usage of mysql query statement analysis Explain shows how mysql uses indexes to process select statements and connect tables. It can help you select better indexes and write more optimized query statements. You can use the explain statement

Tips and notes for using mysql indexes, and tips for using mysql IndexesI. Functions of Indexes In general application systems, the read/write ratio is around, and insert operations and general update operations rarely encounter performance problems.