参考此篇博客
http://blog.csdn.net/z1547840014/article/details/10198237
检查所有库的冗余索引
pt-duplicate-key-checker –user=root –password=cG3sBD9mazGI –host=192.168.27.21
本机
pt-duplicate-key-checker –user=root –password=cG3sBD9mazGI –host=localhost
检查本机冗余索引并输出到index.sql文件
pt-duplicate-key-checker –user=root –password=cG3sBD9mazGI –host=localhost>index.sql
