MySQL

This article introduces how to forget the password of the mysql database server on the linux server. Next we can retrieve the password step by step. 1. log on to the linux server through ssh, and send the kill command to the mysqld server to turn

Many friends who use the mysql database may suddenly stop their mysql database. It is not ruled out that the database will be stopped due to a large number of programmers sending packages to the database, let's take a look at the Cause Analysis and

This article briefly introduces the differences between MyISAM and InnoDB. Based on their features, we can further optimize MyISAM and InnoDB as much as possible. Brief introduction from the official website. Brief Introduction: MyIsam MyISAM is the

I want you to know that data import and import can be implemented using mysqldump, a built-in mysql tool, or a custom program. The following describes two methods. Let's talk about data that is separated by commas (') and vertical bars (|. Many

This article collects a large number of questions from the Internet about how to use mysql indexes to optimize your own databases. It also introduces some situations that cannot be found in index columns. Below are some information found on the

Currently, 1045 means that the user name and password cannot be matched, that is, the password has been forgotten. Below we provide two solutions for changing the password. If you need it, please refer to it. Directly use the username and password

The original server environment uses windows, and then the database backed up by mysqldump cannot be imported into the database in linux. Import always appears: Unknown command '"' Therefore, if you replace all with ', the result still does not

This is just a reference, because mysql performance optimization involves many factors. The best optimization is based on the actual situation of your server and website. If you need it, please refer to it. 1. IntroductionIn the Web application

This is a simple article that uses SQL statements to copy data from one table to another. If you need it, refer to it. Reputation: a and B are both tables -- B tables exist (the two tables have the same structure) Insert into B select * from a if

You will not only encounter this situation in Hibernate, but also in mainstream php. If your database encoding is different from the page encoding, chinese garbled characters may occur. Today, we encountered garbled characters when using Hibernate

The explain syntax is as follows: Explain [extended] select... From... Where... If extended is used, you can use the show warnings statement to query the optimization information after the explain statement is executed. For example, if we execute

How to Use UNIQUE indexes in mysql tutorial Syntax:Unique key 'test' ('xref _ key', 'xref _ dbname ')Unique key 'xref _ key' ('xref _ key', 'xref _ dbname ') The preceding syntax checks whether the combination of xref_key and xref_dbname is a unique

Mysql tutorial quick database tutorial backup and automatic backup bat processing method, the first example below is the bat batch processing method, followed by commonly used SQL data backup commands. @ Echo offEcho.Echo MySQL Database Backup Echo *

Use the where clause with the group by clause Grouping query can have a standard where clause that eliminates undefined rows before forming a group and a computed column function. You must specify the where clause before the group by clause.   $

Find the mysql tutorial configuration fileThe mysql configuration file is/etc/init. d/mysql/my. cnf. (This file does not necessarily exist if it is not ubuntu9.0.4. Since the MySQL installation method you may use is different from the one mentioned

How to create and delete a database in the mysql tutorial Create Table syntaxCreate database ;Look at a simple instance. Mysql>Mysql>Mysql> create database myDatabase;Query OK, 1 row affected (0.03 sec) Mysql>Mysql> drop database myDatabase;Query

The DATE_ADD () function adds a specified interval to a date. SyntaxThe DATE_ADD (date, INTERVAL expr type) date parameter is a valid date expression. The expr parameter is the time interval you want to add. The type parameter can be of the

I. Major changes from 4.0 to 4.1 If an innodb table containing the timestamp field is created in the mysql tutorial from version 4.1.0 to version 4.1.3. You need to recreate the table when upgrading to 4.1.4 and later, because the storage format has

Backup mysql tutorial database tutorial command Mysqldump-hhostname-uusername-ppassword databasename> backupfile. SQL Back up the mysql database in the format of a table with deletionBacking up a mysql database is in the format of a table with

Usage: Concat (str1, str2 ,...) Mysql tutorial> select concat ('11', '22', '33 ');+ ------------------------ +| Concat ('11', '22', '33') |+ ------------------------ +| 1, 112233 |+ ------------------------ + For more details, see