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fix:少写了一个字

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SnailClimb 2018-10-31 15:03:20 +08:00 committed by GitHub
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@ -60,7 +60,7 @@ MySQL中的索引可以以一定顺序引用多列这种索引叫作联合索
```
select * from user where name=xx and city=xx ; //可以命中索引
select * from user where name=xx ; // 可以命中索引
select * from user where city=xx; // 法命中索引
select * from user where city=xx; // 法命中索引
```
这里需要注意的是,查询的时候如果两个条件都用上了,但是顺序不同,如 `city= xx and name xx`,那么现在的查询引擎会自动优化为匹配联合索引的顺序,这样是能够命中索引的.
@ -109,4 +109,4 @@ ALTER TABLE `table_name` ADD INDEX index_name ( `column1`, `column2`, `column3`
- 《Java工程师修炼之道》
- 《MySQL高性能书籍_第3版》
- https://juejin.im/post/5b55b842f265da0f9e589e79