Join is very common in SQL, but usually, the types used are inner join, left join, right join, and outer join. This article introduces what semi join and anti join are, using PySpark as an example.

After setting up Firebase and Google Analytics, Flutter can conveniently send screen_view events. However, this requires manually adding code to each page. I found a way to automate this process with minimal changes.

There seem to be many misunderstandings about Leetcode (or algorithm problems), such as the idea that you need to memorize all the Leetcode problems before going to an interview, or that algorithm questions are like IQ tests (so you can’t improve your problem-solving skills through practice). Many people criticize algorithm interviews for being disconnected from real work, but we can’t control how each company conducts interviews, and discussing this won’t help in passing the…

Python line profiler is a very convenient package that allows you to easily see the time taken for each line of code to execute. However, a fatal flaw is that it does not support profiling in multiprocessing, and there has been an open issue on Github since 2016. Here, I provide a hacky workaround for using line profiler in multiprocessing.