mysql order by two fields

PrefaceIn addition to the regular join statements, there is a class of query statements that are also used more frequently, that is, orderby,group by and distinct. Considering that all three types of queries involve the sorting of data, I put them

The MySQL order BY keyword is used to classify the data in the record. MySQL ORDER BY keyword classified by keyword The ORDER BY keyword is used to classify the data in a record. MySQL ORDER BY syntax The code is as follows Copy

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,

In this article we will look at the optimization of the order BY statement, before which you need to have a basic understanding of the index, and young men and young men who do not know it can start by looking at the index related articles I wrote

By default, MySQL counts null as the minimum value.If you want to manually specify the order of NULL, you can use:Place NULL in the top-most:if (IsNull (field name), 0,1) ASC//ASC can be omittedPut NULL in the lastif (IsNull (field name), 0,1) DSCif

Currently, MySQL databases are widely used in many OLTP scenarios, and there are many different ways to use them. From the database business requirements, architecture design, operational maintenance, and then to the expansion of the migration,

One, MySQL installationInstall MySQL under CentOS Please open: http://www.centoscn.com/CentosServer/sql/2013/0817/1285.htmlIi. several important directories of MySQLMySQL installation is not as if SQL Server is installed by default in a directory,

MySQL order by performance optimization example This article mainly introduces the MySQL order by performance optimization method example. This article explains the principle of order by in MySQL and the three methods to optimize order by. For more

Although order by does not match the ORDER of the index, the index can still be used, as long as the unused index part and all the additional order by fields are included in the WHERE clause. Use the index MySQL OrderThe following queries use

Although order by does not match the ORDER of the index, the index can still be used, as long as the unused index part and all the additional order by fields are included in the WHERE clause.Use the index MySQL OrderThe following queries use indexes