I would second this as being proficient at SQL is a 10x skill. I learned more on the job than in college though. If you want to be good at web app development t

I would second this as being proficient at SQL is a 10x skill. I learned more on the job than in college though. If you want to be good at web app development that means CRUD which means understanding RDBMS and SQL. Even though I work with Rails, I think in SQL when it comes to data relationships. Being able to just join together tables in SQL, get metrics, dive into data issues, etc. without some ORM or layer in between you and the data is a 10x skill since it will likely carry through your entire career as web frameworks, libraries, etc. come into and out of fashion. I would extrapolate this further into knowing the base languages used in whatever you work on. If its web, a fundamental understanding of HTTP, HTML, CSS, JS without frameworks, code generators, etc. will give a solid base to then easily pick up how various languages and frameworks layer on top of the fundamentals.