MySQL

TransactionTransaction is actually a set of database additions and deletions to the combination of operations, it can be understood that when you hit a person 1000 yuan, in the database will be two changes, one is that your money is reduced, the

Copyright NOTICE: This article for Bo Master original article, without Bo Master permission not reproduced.Before explaining the system database, let's look at the evolution of MySQL in data dictionaries:MySQL4.1 provides a information_schema data

--You must have considerable privileges to create a trigger (created TRIGGER), which is sufficient if you are already a root user. This is different from the SQL standard.CREATE Trigger SyntaxCREATE TRIGGER trigger_name trigger_time trigger_eventon

Since the InnoDB preset is row-level lock, MySQL will execute row lock only if the specified primary key is "clear" (only the selected data is locked), otherwise MySQL executes the tableLock (locks the entire data form). For example: Suppose there

[Client]Port = 3306Socket =/tmp/mysql.sock[Mysqld]Port = 3306Socket =/tmp/mysql.sockLog-error =/data/mysql/data/mysql.err#默认存储引擎, the default is InnoDB after 5.5.Default-storage-engine=innodb#默认表的存储引擎, the default is InnoDB after

Mysql:PHP$code=$_post[' Code '];$status= "";$success= "";$scookies= "";Try { $dbname= "Root"; $dbpass= "Root"; $dbhost= "127.0.0.1"; $dbdatabase= "MySQL"; //Generate a connection $db _connect=mysql_connect($dbhost,$dbname,$dbpass); //Select a

mysqldump"--opt Default Options"-A full library-b specifies library-e scheduled task-r stored Procedure functionMYSQLDUMP-UROOT-PROOT-E-r-a Exports are stored procedures, functions, and scheduled tasks based on-aMYSQLDUMP-UROOT-PROOT-E-r-b exports

MySQL has never known much, before the SQL prepared to submit to the production environment before the time, the old staff to help me check the next SQL, let me modify the storage engine, then I used the MyISAM, and later changed to InnoDB. Why to

--Table structure CREATE TABLE ' address ' (' id ' int (one) not NULL auto_increment,' Code_value ' varchar (+) DEFAULT NULL COMMENT ' area code ',' Name ' varchar (+) DEFAULT NULL COMMENT ' zone name ',' Remark ' varchar (+) DEFAULT NULL COMMENT '

As a programmer, the importance of mastering a database is self-evident, MySQL as a widely used database, it is necessary to master it, now and everyone a learning MySQL database!The first step to learning MySQL is, of course, installing and

Mysql************************************Current column ClassName ColumnType displaysize TypeName0:java.lang.integer Columntype:4 One Integer1:java.lang.integer columntype:-6 4 TINYINT2:java.lang.string Columntype:12 0 UNKNOWN3:java.lang.boolean

In general, when the data of our database exceeds the 100w record, we should consider the table or partition, this time I would like to elaborate on some of the methods of the table. First of all, we need to figure out how many tables, the premise

With the long-term use of MySQL, you can fix the table to optimize and reduce disk footprint when optimizing. Easy backup.REPAIR table is used to repair corrupted tables.OPTIMIZE table is used to reclaim unused database space, and when the data rows

First, Index:is to improve the search performance only when we have a very large amount of data, the index can show its advantages!Note: The index, we added after, do not deliberately go to use it, it will automatically take effect1. General index:

Experiment MySQL with the plug-in provided by Google, complete the semi-synchronous replication model;The physical machine is still the Win7 system, the virtual machine is centos7;Master node: 192.168.255.2From node: 192.168.255.3Configure the

MySQL Tutorial master-slave synchronization failed Last_io_error:got fatal Error 1236 from master workaroundThis error is encountered such as: "Last_io_error:got fatal error 1236 from master when reading data from binary log: ' Could not ' find

The operators include four classes: arithmetic, comparison, logical, and bitwise operatorsMySQL can use operators to perform calculations on data in tables, such as age by birth date, etc.The operators include four classes: arithmetic, comparison,

The previous article on some of the MySQL more commonly used SQL statement writing, this document, the usual may use the complex point of the query statement.Complex query statements are commonly found in report queries, elephants before the "use of

SQL format () function usage and simple example, sqlformat The FORMAT () function is used to FORMAT the field display. SQL FORMAT () syntax SELECT FORMAT(column_name,format) FROM table_name; Parameters Description

Complete mysql query statement sorting and mysql statement sorting -- Basic Query Select * from pet -- List specified Columns Select name, owner form pet -- Performs arithmetic operations directly to alias A Field Select sin (1 + 2) as sin -- Where