technical
Drill the SQL questions that get asked in data, backend, and analyst rounds — window functions, subtle join bugs, and reading query plans for real performance wins.
Sample questions
These are the kinds of questions you'll drill. Real mock rounds will generate many more — tailored to the exact JD you paste in.
Given these two tables, write a query to find users with no orders in the last 30 days.
Explain the difference between INNER JOIN and LEFT JOIN with a concrete example.
You run a query and it's slow — how do you diagnose it?
Write a window function that returns each user's running total of spend.
Reading SQL questions isn't the same as answering them live. You need the rep — the pause, the clarifying question, the moment where you realize you forgot the framework. We put you in that exact spot, then show you what a strong answer would have looked like.
Related topics
React
Hooks, rendering, and real-world patterns.
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Scale, trade-offs, and clear reasoning.
Data Structures & Algorithms
Arrays, graphs, trees, and the classics.
Behavioural
STAR answers that actually land.
Leadership
Influence without authority, grown-up feedback.
JavaScript
The language, not just the framework.
Paste the JD, pick your topics, and go. Full session, full feedback, no fluff.
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