how to use if in mysql query

One: Connection query:Connection query is to connect two or more tables according to a certain condition, select the required data, the connection query query two or more tables at the same time, when there are fields representing the same meaning

This article describes how to query logs and slow query logs in MySQL. It also describes how to use the Mysqldumpslow log analysis tool that comes with MySQL. For more information, see I. query logs Query all the queries in MySQL by using "-- log [=

MySQL Query performance optimizationThe optimization of MySQL query performance involves many aspects, including library table structure, establishing reasonable index and reasonable query. The library table structure includes how to design

High Performance MySQL Reading Notes-query performance optimization, high performance mysql For high-performance database operations, it is not enough to design the optimal database table structure and build the best index. You also need to design

A basic tutorial on querying logs and slow query logs in MySQL, I. query logs Query all the queries in MySQL by using "-- log [= file_name. Because all the queries, including all the select statements, are recorded, and the size is relatively large,

For high-performance database operation, it is not enough to design the optimal library table structure, and to establish the best index, but also need reasonable design query. If the query is poorly written, high performance cannot be achieved even

1. Full backup and incremental backup 1.1 full-scale backupFull-volume data is all the data in the database, and a full backup is the backup of all the data in the database.Back Up all libraries:mysqldump -uroot -p123456 -S /data/3306/mysql.sock -F -

Essays-66 Articles-0 comments-MySQL slow query (ii)-Pt-query-digest detailed slow query log one, Introduction Pt-query-digest is a tool for analyzing MySQL slow query, it can analyze Binlog, Gene RAL Log, Slowlog, can also be analyzed via

First we look at the log in MySQL, mainly includes: error log, query log, slow query log, transaction log, binary log;Logs are an important part of the MySQL database. The log file records the changes that occurred during the MySQL database

1. download MySql 1. download MySql Open http://www.mysql.com/downloads/mysql/#downloads download in browser My downloaded version is Red Hat 5 version of http://www.mysql.com/downloads/mirror.php? Id = 407552 Upload the file to the server, or