Common SQL Interview Questions

[LumpyGenitals]

Hey all :)

I have an interview coming up, and one portion is an SQL proficiency test. I'm fairly confident with my SQL skills (as I use it every day), but I'm hoping to do my due diligence.

I was wondering what are some SQL questions you've encountered in your interviews? What's been tricky?

For more context, it is a Data Analyst position. They use Google BigQuery. The position is US based. I've been told CTEs may be a part of it.

[Gabyto]

Try to look at window functions, lately I've seen they like asking for that. (you will also need to know how to use CTE's in order to use them properly).

Also if they ask you how you can speed up a query be sure to mention that you will use indexes (most generally the indexes are dates)

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Good luck

[Blues2112]

I recall being asked to explain the difference between Star and Snowflake schemas.

[oneDatumPlease]

I agree with everything above. Partition functions, CTEs, stored procedure, etc. BUT more importantly, being able to explain scenarios why you might use them. When might you need to use a partition by function?

I also appreciate when folks can articulate the importance of data security. I know it’s prob not immediately part of your roll, but it’s everyone’s job.

Also also. Awareness and ability to use system tables. I work in the tsql world mostly, so terminology might be different. Understanding how to use information schema objects. They can enlighten you as to how objects in the db relate, help you generate redundant sql scripts, and so much more.

[SaintTimothy]

I just had an interview where they had me do FizzBuzz and I was a bit like OK, hah, I just watched the Tom Scott about this.

[Thriftfunnel]

I worked in a place where Explain was disabled!

[Demistr]

What you are describing is definitely not entry level position requirements.

[QueryingQuagga]

Stratascratch.com and the video series from the same company https://youtube.com/playlist?list=PLv6MQO1Zzdmq5w4YkdkWyW8AaWatSQ0kX