Uploaded March 2021 | Updated September 2026, 1 day ago

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In this video, we'll talk about the 5 coding concepts that companies will test you on in data science interviews in 2021. As you guys know, I’m always tracking and collecting interview questions from various companies to better understand what technical concepts you need to know to succeed in interviews and what skills you need to have to succeed on the job. So these are questions that I’ve collected in the first few months of 2021. So they’re as real-time as can be. The companies that I’m sourcing from are Facebook, Postmates, Credit Karma, Ring Central, and Twitch. I’ll introduce the coding concept to know and then show you a real interview question I collected from the company.


Link to the questions:
Share of Active Users: staging.stratascratch.com/coding/2005-share-of-active-users?python=&utm_source=youtube&utm_medium=click&utm_campaign=YT+description+link
Recent Refinance Submissions: platform.stratascratch.com/coding/2003-recent-refinance-submissions?python=&utm_source=youtube&utm_medium=click&utm_campaign=YT+description+link
Paid Users In April 2020: platform.stratascratch.com/coding/2017-paid-users-in-april-2020?python=&utm_source=youtube&utm_medium=click&utm_campaign=YT+description+link
Viewers Turned Streamers: platform.stratascratch.com/coding/2012-viewers-turned-streamers?python=&utm_source=youtube&utm_medium=click&utm_campaign=YT+description+link
Hour With The Highest Order Volume: platform.stratascratch.com/coding/2014-hour-with-the-highest-order-volume?python=&utm_source=youtube&utm_medium=click&utm_campaign=YT+description+link

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👉 Practice more real data science interview questions: platform.stratascratch.com/coding?utm_source=youtube&utm_medium=click&utm_campaign=YT+description+link​

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Timeline:

Intro: (0:00​)
Concept #1 - Categorization, Aggregations, Ratios: (1:10​)
Concept #2 - JOINs, Subqueries, CTEs: (4:22​)
Concept #3 - Subqueries in the WHERE clause: (6:05​)
Concept #4 - Window Functions: (7:15​)
Concept #5 - Date Manipulations: (8:12​)
Conclusion: (9:35​)
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About The Platform:

I'm using StrataScratch (platform.stratascratch.com/coding?utm_source=youtube&utm_medium=click&utm_campaign=YT+description+link​), a platform that allows you to practice real data science interview questions. There are over 1000+ interview questions that cover coding (SQL and python), statistics, probability, product sense, and business cases.

So, if you want more interview practice with real data science interview questions, visit platform.stratascratch.com/coding?utm_source=youtube&utm_medium=click&utm_campaign=YT+description+link​. All questions are free and you can even execute SQL and python code in the IDE, but if you want to check out the solutions from me or from other users, you can use ss15 for a 15% discount on the premium plans.

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Contact:

If you have any questions, comments, or feedback, please leave them here!
Feel free to also email me at nathan@stratascratch.com
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#DataScienceInterview