MySQL

Objective:The previous article has said that the deployment of the original intention, if not clear, you can look at the preface of the previous article or leave a message in the comment area to me.This article mainly introduces the method of

Four ways MySQL gets the self-increment ID1. Select Max (ID) from tablename 2.SELECT last_insert_id () function last_insert_id is not related to table, if you insert data into form A and then insert data into table B Last_insert  _ID will change.

In the MySQL database, the most commonly used engines are 2: InnoDB and Myiasm.First of all:1. Brief introduction of these two engines, and how to choose.2. What are the data structures used by these two engines?1.A.innodb engine, the InnoDB engine

See a good article, transcribed in thisChinese garbled seems to be a program in the eternal topic and difficulties, such as MySQL access Chinese garbled, but I want to do anything, there must be a train of thought, there is a way to know how to

CommandAccess monitor: mysql -u [username] -p; (will prompt password)To display all databases:show databases;Access database: mysql -u [username] -p [database] (will prompt password)To create a new database:create database [database];Select database:

first, the environment preparationJDK 1.8+Hadoop 2.xMySQL 5.xPlease ensure that the above environment is ready before installationSecond, installation1. Download and unzipEnter the directory after decompression, using the current path configuration

MySQL index optimization>mysql only one index can be used for a query. If you want to use indexes on multiple fields, create a composite index.> Smaller data types are usually better: smaller data types typically require less space in disk, memory,

Lab Environment:db1:172.16.1.100Db2:172.16.1.101vrrip:172.16.1.99Steps:Yum-y install MySQL1. Modify the MySQL configuration file for DB1Server-id = 2 #DB1和DB2的id must be different log-bin=mysql-bin #开启mysql的二进制日志功能relay-log = mysql-relay-bin #

//perform the CREATE database operation This. Getexecute (G_con,"CREATE database if not exists newdb"); This. sqladdress ="- H"+ IP +"- u"+ User +"- P"+ Password +"newdb";//Backup of the databasePrivate voidBtn_dump_click (Objectsender, EventArgs e)

One, multiple instances of the application scenario:1, the choice of capital-intensive companiesWhen the company's business visits are not too large, but also reluctant to spend money, but at the same time hope that the different services of the

MySQL Master-slave replication1.mysql Master-slave replication principle:Master logs data changes to binary logs "binary log"Slave copies the binary log "binary logs" of masterto its own trunk log "relay log" . Slave will relay into the log "relay

MySQL commonly used engine mainly have a few, Mrg_myisam, CSV, MYISAM, InnoDB, Memory, NDB, MYISAM, InnoDB is the most commonly used in MySQL storage engine, today the main discussion MYISAM, InnoDB follow up and continue ...First, the

InnoDB and MyISAM are the two most common table types used by many people when using MySQL, both of which have pros and cons, depending on the application. The basic difference is that the MyISAM type does not support advanced processing such as

MySQL Timer task Simple example? 123456789     如果要每30秒执行以下语句：[sql] update userinfo set endtime = now() WHERE id = ‘110‘;  可以给mysql建个定时任务，具体方法如下：[sql] delimiter //   /* 设定语句终结符为 //，因存储过程语句用;结束 */ First, check if the

PHP was installed and Mysql,mysql-server was installed. The MySQL service also started.MySQL is also available in PHP extensions> Php-m | grep MySQLHowever, the execution of the mysql_connect () error says that no such file could be found.The reason

1, display the current encoding informationMysql>show variables like '%character% '+--------------------------+----------------------------+| variable_name | Value |+--------------------------+----------------------------+| character_set_client |

MySql 5.6.14 Win32 bit installation-free decompression configuration tutorial, mysql5.6.14 Mysql-5.6.14-win32 for free installation decompressed version, installation version (http://dev.mysql.com/downloads/installer/5.5.html#downloads) has many

Subquery of the front-end learning database and the sub-learning database* Directory [1] defines [2] comparison operator [3] modifier keyword [4] [NOT] IN [5] to store the query result IN front When querying a database, subqueries are often required

Detailed steps for installing MySql in Linux: linuxmysql The following is a record in my work. We will introduce the installation process and screenshot of installing MySql using officially compiled binary files in linux. This installation method is

Redhat7.1 detailed steps for installing mysql 5.7.10 (graphic description ), To install MySQL under redhat, follow these steps: Mysql directory installation path:/usr/local/mysql Database storage location:/data/mysql Log storage