u/thequerylab

Agreed!. Thanks. I modified it

Can you please elaborate more?

PostgreSQL's docs list SELECT before ORDER BY and LIMIT in its logical processing order:

postgresql.org

You're right about the optimizer, but that's physical execution, not logical order.

Few seconds of silence is totally normal. You don't have to explain every single thought.

I would explain the approach first, then talk through the important parts while coding. Practicing under a timer helps a lot too.

You can use TheQueryLab mock interviews for this - feels more like an actual interview and you get a scorecard after.

Definitely helps with the pressure part.

Thanks. Hope this is helpful!

If your interview is few days away, dont't just read SQL - paractice problems. That's how you find ths gaps before the interviewer does!

You can try TheQueryLab. It has a SQL from Zero to Confident course if you want to learn alongside practice, and there are also quite a few interview-style SQL problems, including harder ones. Might be worth checking out.

https://www.thequerylab.com/

If you’re starting from zero, I’d suggest learning the basics alongside solving problems.

You can check out TheQueryLab’s “SQL from Zero to Confident” course - it’s structured around learning concepts and then practicing them

https://www.thequerylab.com/

The best way to learn SQL is by actually practicing problems, not just watching tutorials.

Start with the basics - SELECT, WHERE, GROUP BY, JOIN, subqueries and then move into window functions, CTEs, etc. Try solving problems yourself first, even if you get stuck. That's where you really start understanding the concepts.

You can enroll for this free SQL from Zero to Confident Course which will help you learn by practicing.

https://www.thequerylab.com/courses/sql-pro-track

The best way to get really good at SQL is to understand the concepts and patterns, not just memorize syntax. That comes mainly from practicing different types of problems and understanding why a particular approach works.

You can create your own sample data and experiment with it, or use a practice platform like TheQueryLab where you can work with different datasets and problems. The important part is to actually write the queries and try to understand the pattern behind each problem.

Yes its supported by most of the databases

I feel all problems with messy data are where you learn the most. Clean datasets make SQL look easy, but NULLs, duplicates, missing records, edge cases, etc. really force you to understand the concepts.

For structured learning and practicing interview style problems you can give it a try on TheQueryLab. https://www.thequerylab.com/

I write queries usually in CTEs. When something is off, I try to do select on each CTE step by step and try to understand which CTE is actually producing the wrong output. Most of the time it turned out to be the Joins. Probably, join on nullable column without proper filter.

For 1 year of experience they usually test concepts like window functions, how rank, dense_rank, row_number, lead, lag works. They usually give some sample dataset and ask you to write the window functions output. Then questions will be around basics of joins (cover all joins) and filtering.
Ensure you practice before your interviews!

Honestly I use SQL way more than I expected when I started doing data work.

There were many times where I thought the issue was in Python/model but later found out it was a SQL join or some NULL values or duplicate rows changing the numbers.

Python gets more attention because it looks more interesting but in real projects a lot of time goes into getting the data right first.

And thats mostly SQL.

For Structured Learning Paths you can take a look at this TheQueryLab. You will for sure love this learning approach

If you're looking for hands-on SQL practice, you can try TheQueryLab. It has a free SQL course plus interactive problems to practise what you learn. It’s especially useful if you’re preparing for data analyst interviews and want to practise SQL in a more practical way. Worth giving it a try!

For data modeling, warehousing and system design - you can take one use case and drop your design to chagpt or any AI tool. For advanced SQL you can practise on TheQueryLab

The best way to learn SQL is to practice what you learn. Always try to code to get deep understanding of each topics. You can give it a try here: https://www.thequerylab.com/

For SQL, avoid just reading a book or watching videos. Learn the fundamentals, then start solving problems regularly. You’ll understand SQL much better when you have to actually write the query yourself instead of just following examples. You can give it a try on TheQueryLab, you will really enjoy this learning

Have a solid foundation in data modeling, data warehousing, advanced SQL, one programming language + DSA, and system design. With 6+ years of experience, also be prepared to go deep into your past projects and explain the trade-offs behind your technical decisions.

Ensure you practice top interview patterns & problems to be more confident

Would say 50 - 50. By trusting solely on AI, it gives too many lines with some junk peice of code which is really not necessary but it really helps in debugging issue.

With year of experience you will be asked more towards Joins. Master all types of joins and practise them. Especially predict the output with all types of joins. Then basics of sorting, ordering, grouping, filtering, ranking.

Only suggestion from my side - do not worry about syntax. Always practise the problems and understand how its working behind the scene and you will master easily. Best of luck!

You can definitely try learning from TheQueryLab https://www.thequerylab.com/