MySQL查询的基本原则

Basic Principles of MySQL Query

查询的基本原则在My SQL查询中很重要,只有在了解原则的基础上,才能写出符合预期的SQL、才能知道所写的SQL到底有没有使用到索引。本文详细介绍My SQL查询中的基本原则。

The basic principles of My SQL query are very important in My SQL query.Only on the basis of understanding the principles,we can write the expected SQL and know whether the SQL has used the index or not.This paper introduces the basic principles of My SQL query in detail.