CMU15-445/645 Learning Record

This repo documents my learning process for CMU15/445: Database Systems (spring 2023).

There are three parts：

1. Lecture note in Chinese: for lec2 - 8，I only record something that I think difficult to understand， for lec9 - 24, I record everything in detail.
2. Project tips: I finish project0-4 without leaderboard optimization，I write down some of the problems and difficulties I encountered during the implementation process.
3. Testcases: The testcases I add base on the results of the online test.