mongo db 자료 모음

http://www.w3big.com/mongodb/mongodb-analyzing-queries.html

https://www.fun-coding.org/mongodb_advanced4.html

https://jaehun2841.github.io/2019/02/24/2019-02-24-mongodb-2/#%EC%97%B0%EC%82%B0-%EB%85%84%EC%9B%94%EC%9D%BC%EC%9D%84-%EA%B8%B0%EC%A4%80%EC%9C%BC%EB%A1%9C-group

https://junho94.tistory.com/11 // mysql 이랑 비교사진있음