Open any unlocked question, read the problem statement and schema, write your query in the in-browser SQL editor, and run it. SqlInt compares your output to the expected result and gives instant feedback — no setup required. Free access starts with the starter question pack.

The question bank mirrors the patterns asked in real data-analyst, data-engineer, and backend interviews — joins, aggregations, window functions, deduplication, and ranking problems — organized by difficulty and company where applicable.

Questions are grouped into Beginner, Intermediate, Advanced, and Expert. Filter by difficulty to practice progressively and track your solved and visited progress as you go.

No — a free account is required to open the SQL editor and solve problems, including the free starter pack. Signup is free and takes about a minute, and logging in keeps your solving progress saved across devices. The mini tools and the learning roadmap work without an account.

Yes — every unlocked question includes a reference solution, an explanation, and progressive hints. Free access covers the starter question pack; the full bank of premium questions (each with its own problem statement, schema, hints, and reference solution) is part of the paid challenge packs.

Yes — these SQL interview questions, also called SQL interview problems, are organized by difficulty from Beginner to Expert. Start with Beginner problems covering SELECT, WHERE, and JOINs, then progress to window functions, CTEs, and ranking problems as you improve.

These SQL interview questions — also called SQL interview problems — mirror real data-analyst, data-engineer, and backend interviews: JOINs, aggregations, window functions, and ranking, organized by difficulty and company.

It depends on your starting level, but a focused plan is typically 2–4 weeks: master SELECT, JOINs, and aggregations first, then practice window functions, CTEs, and ranking problems daily. A consistent 30–60 minutes of solving real questions a day is often enough to reach interview readiness.