I've been on both sides of the SQL interview table somewhere around 20 times in a single job search. The pattern is always the same: candidates know SELECT, they know JOIN, they can write a WHERE clause. Then the interviewer asks them to deduplicate a table, find missing rows, or sessionize an ...
Source: [Dev.to](https://dev.to/datadriven/top-12-sql-interview-problems-for-data-engineers-with-answers-4698)