idage125230age = 25match
mediumGrind 75

In-Memory SQL Engine

Also known as: In-Memory SQL Engine (Custom)

You're implementing CREATE, INSERT, SELECT, and DELETE from scratch—no shortcuts. Interviewers love it because it exposes whether you can follow a spec precisely without drifting. The trap is getting lost in state management halfway through. Keep your table representation explicit and the rest follows.

DesignSimulation
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1Table Builder Warmupeasy
2Part 2
3Part 3

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