*HARD* Apple SQL Interview Question for Data Scientists and Data Analysts (StrataScratch 2029)

Solution and walkthrough of a real SQL interview question for Data Scientist and Data Analyst technical coding interviews. This question was asked by Apple and is called "The Most Popular Client_Id Among Users Using Video and Voice Calls".
Try this question for free on StrataScratch: platform.strat...
Find me on LinkedIn: / frederikmueller
0:00 Intro
0:17 Problem Statement
1:55 Solution Walkthrough
11:26 Outro
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[@allahjoseph]

Thanks for your walk troughs & nice audio !!!

[@Sirigineedi_Navann]

Fantastic one brother 😊❤

[@frederikmuller]

Thank you so much 😍

[@user-gv9yi3hc9u]

thanks bro. will be going for interview soon! This helps

[@shofada]

Thanks for putting this together. The audio quality is good but the volume is low.

[@frederikmuller]

thought so, I’ll fix it with the next recording 👍

[@pushpanthkumar9028]

Does these questions will be sufficient for dataengineering interviews for FAANG or different questions. ?

[@frederikmuller]

I haven’t seen anything harder at the FAANG interviews I went through. They’ll likely test for more breadth of knowledge regarding data pipelines and ETL tools.

[@huhuboss8274]

Isn't this easier (without subquery)? SELECT client_id FROM fact_events GROUP BY user_id, client_id HAVING AVG(IF(event_type IN ("video call received", "video call sent", "voice call received", "voice call sent"), 1, 0)) >= 0.5 ORDER BY COUNT(client_id) DESC LIMIT 1

[@prithivirajankarthikeyan1362]

It is order by count(user_id) DESC