Mysql Left

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Oracle acquired Sun in 09, which is essential for gaining control of MySQL, the hottest open source DBMS. However, the takeover does not seem to have fully achieved Oracle's goal: as early as 08 after MySQL was acquired by Sun, MySQL Kibaki (some founder and top engineers) left MySQL and set up a new company Skysql, and after Sun was acquired by Oracle, A group of senior executives also went out to create the Monty program Ab (MARIADB's parent company). Yes...

Oracle acquired Sun in 09, which is essential for gaining control of MySQL, the hottest open source DBMS. However, the takeover does not seem to have fully achieved Oracle's goal: as early as 08 after MySQL was acquired by Sun, MySQL Kibaki (some founder and top engineers) left MySQL and set up a new company Skysql, and after Sun was acquired by Oracle, A group of senior executives also went out to create the Monty program Ab (MARIADB's parent company). Yes...

Intermediary transaction http://www.aliyun.com/zixun/aggregation/6858.html ">seo diagnose Taobao guest Cloud host Technology Hall This article briefly introduces a simple and easy to use graphical interface backup restore MySQL database method, Use the workbench graphical interface for MySQL database recovery backup. 　　It's helpful to friends who don't like to use the command line. Workbench is MySQL AB ...

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 ...

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 ...

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 is an open source relational database management system, the developer for the Swedish MySQL AB company, is now part of sun company. Oracle announced the acquisition of Sun Company in 2009, so MySQL may become Oracle's products. Because of its high performance, low cost and good reliability, MySQL has become the most popular open source database and is widely used in small and medium Web sites on the Internet. As MySQL matures, it is increasingly used for more large-scale ...

1, use the index to traverse the table faster. The index created by default is a non-clustered index, but sometimes it is not optimal. Under non-clustered indexes, the data is physically stored on the data page. Reasonable index design should be based on the analysis and prediction of various inquiries. In general: a. There are a large number of duplicate values, and often range query (>, <,> =, <=) and order by, group by occurred columns, consider the establishment of cluster index; Column, and each column contains duplicate values ​​can be ...

1, use the index to traverse the table faster. The index created by default is a non-clustered index, but sometimes it is not optimal. Under non-clustered indexes, the data is physically stored on the data page. Reasonable index design should be based on the analysis and prediction of various inquiries. In general: a. A large number of duplicate values, and often range query (>, <,> =, <=) and order by, group by occurred column, consider the establishment of cluster index; b. Column, ...