MySQL

Test under MySQL 5.1.5-alpha to the conclusionLatin1:1character=1byte, 1 kanji =2character,In other words, a field is defined as varchar (200), it can store 100 characters or 200 letters.This should be noted, especially when the field content is

ERROR 1418 (HY000) at line 639:this function have none of deterministic, NO SQL, or READS SQL DATA in its declaration and Binary logging is enabled (youmightWant to use the less safe log_bin_trust_function_creators variable)It turns out that the

1. Install MySQL# useradd-s/sbin/nologin-m MySQL# TAR-XVF Mysql-5.6.41-linux-glibc2.12-x86_64.tar.gz-c/usr/local# mv Mysql-5.6.41-linux-glibc2.12-x86_64 MySQL# Chown-r Mysql:mysql/usr/local/mysql2. Configure the multi-instance profile directory#

InnoDB:Support transaction processing, etc.No lock ReadSupport for foreign keysSupport Row lockIndex of type Fulltext not supportedDo not save the table's exact number of rows, scan the table to calculate how many rowsDelete Table is a row of

Let's look at the simple use of MySQL help with a small example.As shown, there are three columns of data in the grade table, and now I need to add the "id" column to the table. In case I don't know the vocabulary of MySQL add-on, try to solve the

MySQL Log management/etc/my.cnfError log wrong/var/log/mysqld.log "default on"Bin log binary log backup incremental backup DDL DML DCLRelay Log relay Log replication receives replication MasterSlow log slow query log tuning query time exceeds

I. Specifying a pathIn the previous article, the binary package was unzipped, all put in the/usr/local/mysql directory, at the time of installation to specify the base directory and data directory,--basedir=/usr/local/mysql--datadir=/usr/local/mysql/

A. Backup1) Backup tableMYSQLDUMP-UROOT-P Library Name table 1 > E:\backup.sqlMYSQLDUMP-UROOT-P Library Name table 1 table 2 Table 3 > E:\backup.sql2) All tables under the backup libraryMYSQLDUMP-UROOT-P Library name > E:\backup.sql3) backing Up the

Monitor MySQL transaction count#!/bin/bash/usr/bin/mysqladmin -P3306 -uroot -h ‘‘ -p extended-status -i1 |awk ‘BEGIN{local_switch=0;print "QPS Commit Rollback TPS Threads_con Threads_run \n------------------------------------------------------

There are 2 commands to clear the data -- 清空全部数据，不写日志，不可恢复，速度极快truncatetable表名; -- 清空全部数据，写日志，数据可恢复，速度慢deletefrom表名 Business requirements: Clear all test data, leaving only empty data tables1. Querying all table names in the

Database tables:/*Navicat MySQL Data transfersource server:localsource Server version:50640source host:localhost : 3306Source database:springsecuritytarget Server type:mysqltarget server Version:50640file Encoding : 65001date:2018-08-25 22:10

Create a tableFast to the endStudent tableCreate TableStudent (IDint( One) not NULLauto_increment, namevarchar( -), Addressvarchar( +), Primary Key(ID)) engine=InnoDB CharSet=UTF8;INSERT intoStudent (name,address)VALUES('Tiankai Zhi','Tianchang,

Database additions and deletions changeCreate a databaseCreate Database School;Create a tableCREATE table info (ID int not NULL PRIMARY key Auto_increment,name char (TEN) notNull,score Decimal (5,2), hobby int (2));#primary Key PRIMARY key

[Client]port=3306Socket=/tmp/mysql.sock[Mysqld]user = MySQL #使用mysql帐户启动Basedir =/app/mysqlDataDir =/app/mysql/dataport=3306Server-id = 1Socket=/tmp/mysql.sockCharacter-set-server = UTF8General_log = 1Skip-name-resolveBack_log = 300max_connections =

Refer to this blog post:http://blog.51cto.com/12965094/21292671. Download the installation package wget Http://downloads.sourceforge.net/project/boost/boost/1.59.0/boost_1_59_0.tar.gzwget https://

Get a new environment, need to find the relevant configuration, I have a way to relatively fast copy a set of environment.To modify the machine configuration:Virsh related several commands, has been completed, follow-up I re-organize to add ...To

System DatabaseINFORMATION_SCHEMA: Virtual library, do not occupy disk space, storage is the database startup parameters, such as user table information, column information, permission information, character information, etc.Performance_schema:mysql

1. How to use the index of ordinary youthSuppose we have a user table Tb_user, which reads: name Age Sex Jack 22 Man Rose 21st Woman Tom 20

Source Address: https://www.jb51.net/article/140939.htmUsing Scrapy to crawl some of the data on the web, stored in the MySQL database, want to use Django to show the data, see on the web is using the Django models and Makemigration,migrate commands

MySQL version:　　mysql5.6 (Linux General Edition)Installation Environment:MySQL relies on libaio libraries. If this library is not installed locally, data Catalog initialization and subsequent server startup steps will fail. If necessary, install