MySQL

I. Comparison of various installation methods of MySQLUnder the Linux system, there are 3 main ways to install MySQL: RPM installation, binary installation, source installation. The advantages and disadvantages of the three mounting methods are

SummaryWhen I installed MySQL, I encountered some problems and listed the problems.Yum List Mysql-serverThe problem encountered when installing MySQL with the command yum list mysql-server.Probably the meaning Yum was locked by an application.At

After installing MySQL command line Flashback view Service also no MySQL service startedYou installed MySQL No, did not install first, after installing MySQL, In the bin directory, there is a Mysqld.exe, run the program can be added to the MySQL

#!/bin/bashDpath= "/mysql_backup" mydays= "7" username= "root" mysql_pwd= "Redhat" xmysql= "/application/mysql/bin/mysql-u$ USERNAME-P${MYSQL_PWD} "xmysqldump="/application/mysql/bin/mysqldump-u$username-p${mysql_pwd} "today= ' Date +%Y%m% d '

The following are the corresponding relationships for SQL Server, JDBC type, and Java types: S SQL Server Type ype JDBC Type JDBC Type Java Type Java Type Mock Default Value Description Description

In MySQL, varchar and char types must specify the length, and the int type does not need to be specified.For exampleSET NAMES UTF8;DROP TABLE IF EXISTS ' Content_Type ';CREATE TABLE ' Content_Type ' (' ID ' BIGINT not NULL auto_increment,' Name '

/etc/my.cnf /etc/mysql/my.cnf /usr/local/mysql/etc/my.cnf ~/.my.cnf Other my.cnf under custom paths, for example:/DATA/MYSQL/YEJR_3306/MY.CNF Whether it's a mysqld server-side program or a MySQL client program, you can use the

Environment: HE3 Main Library, HE1 from the libraryhe1:192.168.1.248he3:192.168.1.250from the library my.cnf Add the following parameters and restart the database:Read_only=1Log_slave_updates=1 (it is recommended to open, from the library record

Role: Constraints are used to ensure data validity and integrity. Define PRIMARY KEY constraint PRIMARY KEY constraint primary key: Information record a field can uniquely differentiate other information records, this field can be primary key

Ruchunli's work notes , a good memory is worse than a bad pen MySQL5.6.17 Study Notes (i) Database optimization ideashttp://luchunli.blog.51cto.com/2368057/1705491MySQL5.6.17 Study Notes (ii) Index Introductionhttp://luchunli.blog.51cto.com/236

wget http://mirrors.sohu.com/mysql/MySQL-5.6/mysql-5.6.27.tar.gz Yum install-y CMake Of course can also download the source package installation, for the convenience of Yum installed Useradd-s/sbin/nologin MySQL Tar zxvf mysql-5.6.27.tar.

MySQL's varchar fields are sorted by numberToday, I encountered a question about sorting, when a table was built, and the wide fields in the table were stored with varchar, because the unit might be stored so it was not stored in Int. But later

MySQL changes the character set of an existing data table, preserving the original data content Original URL: http://blog.csdn.net/learn_2/article/details/6460370Environment: In the beginning of the application does

Use of wildcard characters in MySQL queries Wildcard characters are often used in MySQL queries, and there is a difference between MySQL's wildcard characters and Pgsql (discussed later), and regular expressions can

MySQL Query record if there is a timestamp field, the view results inconvenient, can not immediately see the meaning of the timestamp represents, now provides the MySQL format change time function, you can easily see the time after the format.1. The

How to install MySQL database, do not say here, just say its master-slave copy, the steps are as follows:1, the master-slave server for the following actions：1.1. Consistent version1.2. Initialize the table and start MySQL in the background1.3,

How to install MySQL database, do not say here, just say its master-slave copy, the steps are as follows:1, the master-slave server for the following actions:1.1. Consistent version1.2. Initialize the table and start MySQL in the background1.3,

MySQL functions cannot be created. MySQL functions cannot be created, which is a very troublesome problem. The following provides you with a solution to this problem. If you have encountered similar problems, take a

Difference between DISTINCT and group by, distinctgroupby Difference between DISTINCT and GROUP > DISTINCT is used to retrieve duplicate items in the query results, while group by is displayed by group. The purpose of the former is to remove the

MySQL trigger Update failed to trigger Insert, mysqlinsert To display the historical records of tables with status updates only, you need to create a trigger in the original table to write the updated content to another table at the same time. So