Ace SQL Interviews: A Data-driven Approach for Data Scientists

Top N is the most frequently presented SQL question in interviews. In this video, I hope to help you understand how to answer questions like, “What are the Top 5 highest-rated movies?” and “What are the Top 3 highest paid employees per department?” I’ll demonstrate the problem using an example, and fill you in on how to modify the query when there are ties in the ranks.

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Contents of this video:
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00:00 Introduction
01:22 Get My Notion Pages!
01:44 Top N Problem
02:15 Sample Questions
02:33 Top N Records
03:02 LIMIT and OFFSET
03:47 Window Functions
05:30 Top N Per Category
07:40 Top N Per Category With Ties
08:50 Topic for Next Video

[brittanybutterworth]

Really good content - I had to watch it over twice because the video was so technically dense. I really appreciate this kind of problem because its easy to see where you could logically be asked to do this type of query on the first day of the job rather than a nebulous situation. Thanks so much for making these videos!! ♥

[TheACG]

Hi Emma, I bombed a coding interview just last week with a Top N question requiring window functions. Never again! Also, just wanted to say that I'd like to follow you on LinkedIn, but afraid that people at my company will see that I liked/follow a person giving advice on how to interview for jobs, which might tip them off on my job search. All this to say that there may be others like me who are closet followers :)

[nehusingh]

Hi Emma, your videos and contents are always super resourceful. If you ever have time please do a video on Correlation and how to handle strongly Correlated feature.

[davidskarbrevik]

Nice concise explanations. Looking forward to a part 2

[krzysztofjarek]

Thanks, great video - clear explanation ☺

[romangirin]

cool explanations with examples which easy to grasp

[SanuSatyam]

Nice Session. Your explanations are precise and clear.
Can you please upload the notion page of this video?

[mhh]

7:35 where does "rating" column come from in the tables 'avg_ratings' and 'rating_rank'? Shouldn't it be 'avg_rating'?