Show Variables Mysql

Here's an excerpt of the background, followed by a record of the operations I migrated from MySQL 5.5.31 to mariadb 5.5.31 on CentOS 6.4. 　　Finally, I found a better way to migrate. 1. Background introduction MySQL is the world's most popular open source relational database. 2008, Sun acquired MySQL. Then, in 2010, Oracle bought Sun, and MySQL fell into Oracle's hands. Oracl ...

This article mainly introduces the MySQL slow query analysis method, some time ago, I have set a record in the MySQL database to query SQL statements slower than 1 second. Think of a few very set method, there are several parameters of the name of life and death memories can not afford, so re-sort it yourself as a note. For troubleshooting bottlenecks to find out the performance, the most easy to find and solve the problem is MySQL slow query and did not have to use the index query. OK, began to find out MySQL implementation is not "cool" SQL statement. ...

MySQL tutorial automatic stop cause analysis and solution Start menu-run-services.msc find MySQL service and double-click the Recovery tab to fail for the first time: default is "Do not operate", change to "restart service". Adding "0" at the bottom of "Restart Service: ___ Minutes" means that the service restarts immediately if it terminates unexpectedly. Click OK to make the settings effective. At this point you end the MYSQL-NT process in the Task Manager, you will find that the end is not lost but pay attention, so mys ...

MYSQL Based database installation is complete, the default maximum number of connections is 100, the general flow slightly larger forums or websites this connection is not enough, increase the default MYSQL connection method there are two ways: Enter the MYSQL installation directory Open MYSQL Configuration file my.ini or my.cnf Find max_connections = 100 Modify max_connections = 1000 MYSQL Based services can be restarted Method two: MySQL ...

In the development of friends especially and MySQL have contact friends will encounter sometimes MySQL query is very slow, of course, I refer to the large amount of data millions level, not dozens of, the following we take a look at the resolution of the query slow way. -Often find developers looking up statements that are not indexed or limit n, which can have a significant impact on the database, such as a large table of tens of millions of records to scan all, or do filesort, and the database and server IO impact. This is the case above the mirrored library. And ...

First, the importance of the index The index is used to quickly find a column in a particular value of the line. Instead of using an index, MySQL must start with the first record and then read the entire table until it finds the relevant row. The larger the table, the more time it takes. If the table in the query column index, MySQL can quickly reach a location to search the middle of the data file, there is no need to see all the data. Note that if you need to access most of the rows, sequential reads are much faster since we avoid disk searches. If you use Xinhua Dictionary to find "Zhang" the Chinese characters, do not use the directory, then ...

Usually when we use the MySQL database, often because of operational errors caused by data loss, MySQL database backup can help us to avoid due to various reasons, data loss or other problems with the database. First, the data backup shortcut Because this method has not been the official official document validation, we tentatively called the experiment. Purpose: Backup hostA host a MySQL database backup TestA, and restored to the hostB machine in the test environment: Operating System: WinNT4.0, Mysql3.22.34, phpM ...

In this lesson, we want to learn how to increase the intelligent processing capacity of the Web page. Basic functions Welcome to the third and final lesson of this tutorial. If you've learned the first and second lessons, you've mastered the basics of installing and programming MySQL and PHP. Here are some of the other functions of PHP that might be useful to you and make your development process simpler. 　　First, let's look at the document. You should know some basic concepts of the header file, right? The header file is an external file whose contents are included in the main program. ...

In real life, backing up the database regularly is a very important thing. 　　When we use MySQL, there is a lot of choice in database backup, and this article will show readers how to use MySQL's mysqldump to back up the database. First, the importance of data backup work, if the accidental deletion of important files or directories, then the result will be miserable. Especially when the data that is accidentally deleted involves important customers or key projects, and the data can't be recreated easily, it doesn't have to be what I say you can imagine. Unfortunately ...

Modify the maximum number of connections mysql The maximum number of connections mysql default is 100, the maximum can reach 16384. Setting method: Method 1 / etc path, find the MY.INI file, modify [mysqld] followed by: set-variable = max_connections = 500 Save and exit, restart MYSQL, OK! Method two in the MYSQL running environment, the Executive Set global max_connection ...