MySQL

Brief introduction The project uses MSSQL as a database, but because the SQL Server is a bit more expensive and the concurrency connection is a little bit worse, migrating data to MySQL, incidentally, and the problem.

MySQL Sort by Chinese name  sql code  www.2cto.com  /*  navicat MySQL Data Transfer    source Server        : local  source Server version:50022  source Host         &NBS P : localhost:3306  source Database      : Test    target Server Type    : MYS

Today learn how to use Java to manipulate the database, tutorial video There are two methods, one is JDBC-ODBC Bridge connection, one is the direct use of JDBC. I chose the latter.But not as simple as the tutorial, the tutorial uses SQL Server 2000,

In other words, I built a database called AC in MySQL, but I can't find its storage location, how is the database stored in MySQL, and is there a log file and data file like SQL Server?MySQL database on the system is in the form of a folder, you

--Single field indexCREATE INDEXLast_name_index - onemployee_tbl (last_name); Query OK,0Rows Affected (0.06sec)--Unique indexCREATE UNIQUE INDEXLast_name_unique_index - onemployee_tbl (last_name); ERROR1062(23000): Duplicate Entry'GLASS' for Key '

Using the root user Perform: Grant Select,insert,update,delete on projects.* to ' test ' @ ' percent ' identified by ' test '; Results: ERROR 1044 (42000): Access denied for user ' root ' @ '% ' to database ' XXXXX ' Workaround: User MySQL; SELECT *

MySQL Master-slave configurationConfigure to prepare the database to be configured for master-slave synchronization, the master-slave server must have the same databaseFirst, configure the MySQL master server[[email protected] ~]# vim /etc/my.cnf....

1. Load DriverString drivername= "Com.mysql.jdbc.Driver"; Database-driven Classpathtry{Class.forName (drivername); Create a driverSystem.out.println ("Create driver success!") ");}catch (ClassNotFoundException e) {E.printstacktrace ();}2. Define

A comprehensive technology for MySQL optimization, mainly including The design of the table is rationalized (in accordance with 3NF), some of which need inverse paradigm; http://www.cnblogs.com/ChaosJu/p/4543210.html SQL statement

MySQL Import DataThere are two simple ways to import MySQL-exported data in MySQL. Importing data using LOAD dataThe load data infile statement is provided in MySQL to insert the information. The following instance will read the file Dump.txt

First, MySQL data backup and recovery1. Data backup method:Physical backup: CP Tar mysqlhotcopyLogical backup: mysqldump MySQLBackup policy:Full backup differential backup incremental backupCommon backup combinations:Full backup + differential

The InnoDB engine differs from the MyISAM engine. MyISAM InnoDB row-level lock non-object security things security full-text indexing full-text

Because the business needs to count a batch of data, using the time operation function and stored procedure about MySQL, the problem has been basically solved, the process is recorded:1. MySQL statement does not support the direct use of loops, the

Method one: After ignoring the error, continue syncingThis method is applicable to the case that the data of master-slave database is not very different, or the data can not be completely unified, the data requirements are not strict.Stop

Mysql Database Error Solution ERROR 1046 (3D000): No database selected Error Description: no database is selected ---- Cause: the corresponding database is not opened (operations on creating tables and tables must be performed under the database)

Bug #19528825 "unable to purge a record ", Overview: In the production environment, when insert buffer is enabled (innodb_change_buffering = all), some instances occasionally encounter the "unable to purge a record" error. This is actually an old

MySQL Horizontal Split (Reading Notes)1. Introduction to horizontal split In general, a simple horizontal split mainly refers to distributing a table with extremely ordinary access to multiple tables according to certain rules of a field. Each table

Mysql allows remote login configuration Two steps: 1. Change the "host" in the "user" table in the "mysql" Database (you can log on remotely after this step) X: \> mysql-u root-pvmwareMysql> use mysql;Mysql> update user set host = '%

(1) Positioning of SQL Performance problems during mysql OptimizationOverview When we face a problem, we first discover the problem and then solve the problem. This article mainly addresses how to locate the problem. Solution 1. Use show status to

MySQL Query OptimizationThere are many things to optimize database queries. The basic principles are as follows: reduce the disk I/O count that occurs during database queries. Use indexes to avoid full table traversal and scan to reduce the amount