Coding Concepts in Data Science Interviews in 2021 (Facebook, Twitch, Postmates)

[@mosherchtman]

I'm a little confused - 5:40 most recent, shouldn't use the MAX function instead of MIN?

[@BBBBBBAAAl]

Thank you Nate! Great content as usual, I really hope you keep going and I thank you alot.

[@stratascratch]

Yup, will keep this series of interview questions going. I come out with a set of questions every month so I want to make sure those are communicated on KZbin. Over time we'll go over the trends and concepts tested on interviews as soon as I am able to analyze the trends.

[@subinivi]

Thanks a lot. Much appreciated

[@TheCazz10]

Very helpful, thank you

[@thebestofbests7746]

You are really doing a great job, cleared most of my concepts.

[@stratascratch]

That's great. Hope the other videos were also helpful

[@vrajpatel8256]

Great work sir, I finally found what I was looking for on your channel.

[@stratascratch]

Thanks for watching! So this is the type of content you'd like to see more of?

[@vrajpatel8256]

@@stratascratch Yes sir!!

[@jimwoodward7293]

Thanks Nate - very informative content.

[@kritiverma1342]

Hi Nate, great content. I was wondering if you have any video on nested subqueries or on query optimization techniques.

[@stratascratch]

Hi! Thanks for watching. No specific video on nested queries but many of my video shave nested queries. And towards the end, I talk about optimization on most of my SQL videos.So I think that might help.

[@ItzLarry]

Super useful content Nate! Which of your previous videos would you recommend I watch/study for a SQL interview for a company like Square? I have my interview pretty soon and I haven’t found many tips/examples online about Square

[@stratascratch]

Ah, unfortunately, I don't have any Square interview questions on youtube. I don't even think I have too many on my platform (platform.stratascratch.com). Check out both the coding and non-coding sections. There might only be a handful of them. I would recommend doing questions from companies in the same industry which might be helpful. And companies from tech like Twitter since the talent pool they source from is similar.

[@majorcemp3612]

Is count(cas when x='y' then 1 else null end) Equivalent as sum(cas when x='y' then 1 else null end) ?

[@stratascratch]

Yes, I think so since you're using NULLs in the sum(). However, not sure if that would work since standard is to use 0 in the sum(). In which case, it would not be equivalent. Here's a resource on it stackoverflow.com/questions/46894050/difference-between-count-and-sum-within-an-aggregate-case-statement/46894311

[@majorcemp3612]

@@stratascratch okay, nice to know thanks :D

[@t2udu]

I learned sql through the sqlite 'flavor' so I do understand what's going on. Is there a particular flavor that's popular in interviews?

[@stratascratch]

For interviews, you can use any flavor (in my experience) so sqlite is totally fine. At the job, most companies have industry grade db engines so you'll see HIVE and Snowflake which most people don't have access to so that's why they allow any sql engine on interviews.

[@t2udu]

@@stratascratch Thanks for clearing that up!. Keep up the awesome videos.

[@callravik]

I had an interview with FB a couple of years ago. My interview ended with one question. How do you order by data without using order by clause in SQL? I could not give a satisfactory answer which ended my interview for a Data Architect. I tried to get more information from the interviewer but in vain. She was arrogant and condescending. I ran it by Tom Kyte, he said I was better off not working for that manager. I was curious since then, if any of you got these kinds of gotcha questions.

[@stratascratch]

I never had someone ask me that question before in an interview. But I guess you could create an index or ranking column that would give an order to the rows? I'm not a data architech so my db knowledge isn't as good as traditional architects. Looks like you dodged a bullet!

[@pastramiking]

Is it just me or does data science have less and less to do with modeling each year?

[@johnwig285]

That's because modelling is just a tool, a means to an end. Data Science is about deriving insights to create a business impact. Not everything requires models.

[@mikemihay]

Thank you!

[@stratascratch]

Thank you for watching!

[@rahidulislam5129]

Thank You

[@stratascratch]

Thanks for watching!

[@kenehrman342]

So, I know all that SQL stuff, that doesn't make me a data science candidate does it? Surely there is more to it than that.

[@stratascratch]

No not at all. SQL is just a component of data science. But the questions that I go through are data science type. I should probably start covering other data science topics on this channel =)