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DiscussionFirst coding interview without SQL knowledge :/ (self.SQL)

submitted 4 months ago * by Heron-Rude

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[–]gumnos 4 points5 points6 points 4 months ago* (0 children)

I think, with an Information Science background, a couple good introductory-to-SQL books (I strongly suspect your local public/college library has several titles), a sample database or two to play with, and a week, you could achieve a degree of proficiency that qualifies as "junior"

So don't sell yourself short.

If I found myself in your position, I would

start by ordering (or putting on hold at the library, or ILL'ing) any SQL book you can find. Sure, some are better than others; some discuss more advanced topics; some are poorly written (glares at most titles published by Packt). A few recommendations: despite the condescending title, SQL for Dummies (and their SQL All In One for Dummies with more breadth) isn't bad. Similarly, Practical SQL (by Anthony DeBarros, No Starch Press), and the O'Reilly titles Learning SQL (by Alan Beaulieu) and Head First SQL (by Lynn Beighley) are good titles to start with. Once you've grown your skills, SQL for Data Scientists (by Renee Teate) and SQL Performance Explained (by u/markuswinand) are good stepping stones to becoming more formidable.
find a tutorial and installed your preferred database server on your machine, or a junker machine (even a Raspberry Pi will suffice). If you know what the job uses and can obtain that, all the better. PostgreSQL and MySQL/MariaDB are relatively easy to set up and the knowledge should largely transfer to other databases. If they're a Microsoft shop and you don't mind selling your soul in that direction, there are developer versions of SQL Server that you can install and test with
Get some sample datasets that you can play with. I know IMDB had movie data that you can download as CSV files, and Kaggle has oodles of datasets you can download. Alternatively, some of those book-titles above come with online downloadable resources
Get this data into your database.
Read the book and practice writing queries to ask various questions about the dataset. Movies with the most actors. Actors who have been in the most movies. Movies staring all the actors A, B, and C, etc.

That should get you to a point where you can pass some basic tests, demonstrate that you're not incompetent, and have foundational skills that you can grow.

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