MySQL

The last time I forgot to compress the package how to install the MySQL service, hope not to forget againThere are two ways to install MySQL on Windows, using Mysqlinstaller, using compressed filesSome points to be aware of1, unzip the directory is

I. Master-slave replicationMySQL replication is done by copying the data from one primary (master) server to the other host (slaves). There can be many from the server. And the principle of replication is not related to the MySQL binary log. The

Start TRANSACTION; Start of transaction processingUPDATE a set money =money-2 where id=1;UPDATE a set money=money+2 where id=2;commit;//End of transaction processingStart transaction;//transaction processing beginsUPDATE a set money =money-2 where

#mysql主库配置添加:# Cache User table and index data of the most important cache space, generally recommended 50%~80%, but should be based on the actual situation of MySQL server, if running other#的应用服务或者有 the MyISAM table, you need to subtract thememory

Character typeFirst we will talk about the concept of character sets, which refers to a set of characters, and character encoding refers to the encoding format of a character, so the relationship between the two can be described, for example:

A transaction is divided into 4 levels:1.read Uncommitted ( unread): Cannot avoid dirty reads, non-repeatable reads, virtual reads (phantom reads)2.read committed ( read-committed ): can avoid dirty reading3.repeatable committed ( repeatable read):

A few years ago, Stephane Combaudon wrote a blog post, "10 performance configuration items to tune after installing MySQL" (Ten MySQL performance tuning settings after installation) content covered MySQL 5.1, MySQL 5.5 and MySQL 5.6 are some of the

MySQL Problem small Summary1.MySQL Remote Connection Error 2003 (HY000): Can ' t connect to MySQL server on ' IP ' (111) issueTypically, the MySQL configuration file is configured with the/etc/mysql/my.cnf[Mysqld]bind_address=127.0.0.1In this case,

#_ *_coding:utf-8_*_import mysqldbdbhost = "192.168.89.101" DBUSER = "root" dbpasswd = "1qaz#edc" DB = "soms" PORT = 3306CHARSET = "UTF8" #建立与数据库的连接conn = MySQLdb.connect (Host=dbhost, User=dbuser, passwd=dbpasswd, Db=db, Port=port, Charset=charset)

One, createCREATE Index to add a normal or unique index to a table.CREATE INDEX index_name ON table_name (column_list)CREATE UNIQUE INDEX index_name ON table_name (column_list)1) Build Multiple indexesCREATE INDEX Table Name _ Field name 1_ field

If the table defines a varchar field and the number is passed in, an implicit conversion occurs.1. Table DDL2, the SQL to pass int3. String-Passed SQLTake a closer look at the table structure, the field type of RID:　　When the user comes in int,

A subquery (subquery) refers to a SELECT clause that appears within other SQL statements.For example:SELECT * from t1 where col1= (select col2 from T2);where select * from T1, called Outer query/outer Statement (outer query)Select col2 from T2,

Main ip:192.168.1.1From ip:192.168.1.2Main: #vim/etc/my.cnfAdded: Binlog-do-db=charlesdb # #自己创建的同步数据库, this is charlesdb.Binlog-ignore-db=mysqlModified: Server_id=1 # #server_id要不同650) this.width=650; "Src="

Xmapp integrated LAMPP under MySQL does not set the environment variable before, to use MySQL required CD to/etc/lampp/bin directory, perform mysql-uroot-p123456 to access, set environment variables, Arbitrary in a directory can be directly executed

MySQL efficient method of using Rand random query recordsAlways thought that MySQL randomly query a few data, useSELECT * from ' table ' ORDER by RAND () LIMIT 5You can do it.But the real test is that it's very inefficient. A library of more than 150

MySQL parameter table_open_cache settingsThe default value of table_open_cache for MySQL is 64. This value is too small. If max_connections is large, it may cause performance problems.To avoid thread interference, each thread accessing the table

MySQL full-text search and mysql full-text search We can use the match against statement in mysql DATA to solve the problem of full-text Chinese search. Let's take a look at an example: SELECT * FROM v9_search WHERE 'siteid' = '1' AND 'typeid' = '

MySQL master-slave replication and master-slave Replication1. Introduction As one of the most widely used databases in the world, MySQL is free of charge. However, it cannot be ignored that its own functions are indeed very powerful. With the

Preprocessing statement for adding data to PDO and pdo preprocessing statement 1. Add page add data code: name: 2. Processing page(1) create a PDO object$ Dsn = "mysql: dbname = mydb; host = localhost ";$ Pdo = newpdo ($ dsn, "root", "123 ")

MySql installation and use text tutorials, mysql installation text tutorials MySQL is a relational database management system developed by MySQL AB in Sweden and currently belongs to Oracle. MySQL is an associated database management system that