更新 '_posts/mysql.md'

_posts/mysql.md

@@ -1,7 +1,7 @@
 ---
 title: MYSQL
 date: 2020-06-15
-cover: https://static.jqwei.com/blog/img/text/5.png
+cover: https://static.jqwei.com/blog/img/text/2.png
 ---
 ## MYSQL相关