12、MySQL菜鸟教程
http://www.runoob.com/mysql/mysql-data-types.html
3、MySQL Workbench怎么使用及其使用教程
https://jingyan.baidu.com/article/3f16e003c2da162591c103e4.html
怎样备份/还原MySQL数据库 之 MySQL Workbench
https://jingyan.baidu.com/article/870c6fc32ea48cb03fe4beaa.html
MySQL char与varchar的差异
https://www.cnblogs.com/zejin2008/p/6020030.html
MySQL之——GROUPBY分组取字段最大值
https://www.2cto.com/database/201701/591542.html
sql的行转列(PIVOT)与列转行(UNPIVOT)
https://www.cnblogs.com/linJie1930906722/p/6036714.html
MySQL的Limit详解
https://www.cnblogs.com/acm-bingzi/p/msqlLimit.html
MySql Order By 多个字段 排序规则
https://blog.csdn.net/xlxxcc/article/details/52250963
mysql 实现oracle start with connect by递归
https://www.cnblogs.com/interdrp/p/3978018.html
oracle connect by用法篇
https://blog.csdn.net/wang_yunj/article/details/51040029
ORACLE和MYSQL函数
https://www.cnblogs.com/justinhits/p/6232750.html
