A
Sword refers to the path in the offer12 matrix https://blog.csdn.net/hagle_wang/article/details/105084539
R
https://mp.weixin.qq.com/s/4b-RLBq1IrTvMuLMEpeTPg
mainly analyzes the trade-off between kafka and rabbitmq. I
learned that the underlying layers of kafka and rabbitmq are very different.
One is message middleware, and the other is a distributed streaming system.
T
The AB table in mysql is related by the field xx. If you want to view the data that exists in A but does not exist in B,
you can use left join on A .xx = B.xx and (B.xx is null OR trim (B.xx) = '' );
Be careful not to use where to use and because where is to filter the entire result set
S
Cache and channel in NIO https://editor.csdn.net/md/?articleId=105086029
