mysql order by two columns

The main purpose of this article is to demonstrate how LookMySQL joins. by "look at" I mean how to see through MySQL's eyes, so-to-speak. this task is fundamentally different from the rather straight-forward tasks of how to do joins or how to index

In some cases, MySQL can use an index to satisfy the order by clause without additional sorting. The where condition and order by condition use the same index, and the order by order is the same as the index order, and the order by field is both

MySQL Order By Principle and Optimization 1 IntroductionFor business (MySQL) DBAs or business developers, order by is a common business function that sorts the results based on specified fields to meet front-end display requirements. However,

MySQL常用指令，java，php程序员，数据库工程师必备。程序员小冰常用资料整理MySQL common commands (for reference)The most common display commands are:1. Display the list of databases.show databases;2. Display the data table in the library:Use MySQL;Show tables;3, display the

Let's just look at the example. Try it by yourself Mysql> select * From tb_clothes; + ---- + -------- + ------- + ------------ + --------- + | ID | Name | price | Total | date | Address | + ---- + -------- + ------- + ------------ + --------- + | 1

Because the database records may need to be reordered. In this article, I will talk about two ideas to improve the query efficiency of Order By statements for your reference. In MySQL databases, Order by statements are frequently used. However, it

Because the records of the database may need to be reordered. In this article, I will talk about improving the order BY statement query efficiency of two ideas for your reference. In the MySQL database, the ORDER BY statement is used more

MySQL ORDER BY syntax The code is as follows Copy Code SELECT column_name (s) from table_name ORDER BY column_name NOTE: The SQL statement is a "letter case insensitive" statement (it does not distinguish

MySQL index details, MySQL index detailsI. Introduction to index basics 1.1 In MySQL, indexes are also called keys. They are a data structure that the storage engine uses to quickly find records. Indexes are critical to good performance. Especially

This article transferred from: HTTPS://WWW.TUICOOL.COM/WX/2EMBFMQObjectiveTalking about MySQL query optimization, I believe you have a collection of artifice: You cannot use SELECT *, do not use null fields, reasonably create an index, select the