From ea8348fabb0a5f539737b2181402a90f5cfaeda9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=B0=8F=E6=9F=922012?= <345849402@qq.com>
Date: Thu, 13 Sep 2018 16:51:41 +0800
Subject: [PATCH] =?UTF-8?q?=E6=9B=B4=E6=96=B0=20MySql=5Findex.md?=
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---
 数据库/MySql_index.md | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/数据库/MySql_index.md b/数据库/MySql_index.md
index 55f09e8..2c6e430 100644
--- a/数据库/MySql_index.md
+++ b/数据库/MySql_index.md
@@ -68,4 +68,8 @@ mysql查询只使用一个索引，因此如果where子句中已经使用了索
 select * from users where YEAR(adddate)
 ```
 #### 不使用NOT IN和操作
-NOT IN和操作都不会使用索引将进行全表扫描。NOT IN可以NOT EXISTS代替，id3则可使用id>3 or id
\ No newline at end of file
+NOT IN和操作都不会使用索引将进行全表扫描。NOT IN可以NOT EXISTS代替，id3则可使用id>3 or id
+
+## 参考阅读
+
+[MySQL索引背后的数据结构及算法原理](http://blog.codinglabs.org/articles/theory-of-mysql-index.html)