I actually did the “brew uninstall …” statement first before I reach for help. The reason was that the uninstallation only deleted the download package and did not seems to clean up all the long list of stuff /usr/local/bin or /usr/local/var. So out of curiosity I try to “reinstall” Mongo Shell again with the “brew install” again. Only that the second time brew did not work and came up with a
Warning: mongodb/brew/mongodb-community-shell 4.2.0 is already installed and up-to-date
To reinstall 4.2.0, run
brew reinstall mongodb-community-shell
So I thought the uninstallation process only deleted the download packages but did not do a real uninstall of mongo shell. It’s no big deal to leave mongo shell in my system but I am very curious in how to properly clean it up. Homebrew does a great job in spoiling people like me not to understand how things work underneath.