mysql example queries

The following articles mainly introduce three very useful methods to optimize MySQL database queries. We all know that in MySQL database query optimization queries, database applications (such as MySQL (the best combination with PHP) actually mean

**************************************** ****************** The first part is to build a multi-mysql service on a server. **************************************** ****************** I. xuyan There is a mysqld_multi command in Mysql that can be used

Run multiple MySQL services on the same machine Run multiple MySQL services on the same machine **************************************** ****************** The first part is to build a multi-mysql service on a server. *****************************

Similarly, using the goods table to practice subqueries, the table structure is as follows:All data (cat_id associated with category.cat_id):Category table:Mingoods (test when connecting queries)First, sub-query 1,where sub-query: The result of the

-- Add users and groups [root @ zlmlocal] groupadd [root @ zlmlocal] useradd-gmysql-ssbinnologin-doptmsyqlmysql -- create a directory [root @ zlmlocal] mkdirdatamysqlmysql_3306 {data, l -- Add users and groups[Root @ zlm local] # groupadd [Root @

This article mainly introduces the MySQL log settings and viewing methods, the need for friends can refer to the following MySQL logs: error log:-log-err query log:-log slow query log:-log-slow-queries update log:- Log-update binary log:-log-bin by

MySQL Study Notes summary, mysql Study Notes Slow SQL: A Query whose execution time exceeds the specified time range is called a slow query.In MySQL, how does one record slow SQL statements?A: You can set the following information in my.

Excerpt from: http://www.jb51.net/article/33736.htmWith the help of explain, you know when to add an index to the table to use the index to find records and make the select run faster.If some problems arise due to improper use of the index, you can

Database query set two database tables The first table, user, consists of: user_id username Age Sex 1 Alps1992 22 Mans The second table toy

From: The asynchronous implementation of MySQL query via the co-processObjectiveRecently studied Ben Linders's speech and learned that Facebook's MySQL query can be asynchronous to improve performance. Because Facebook was implemented earlier, they