Intermediate~3h
Transactions & Concurrency in SQL & DatabasesInterview Readiness Check
ACID, isolation levels, dirty/phantom reads, deadlock prevention, SELECT FOR UPDATE, optimistic locking.
acidtransactionisolationread committedrepeatable readdeadlockselect for updateoptimistic locking
Learning path
Try a sample question
In ACID, what does Isolation guarantee?
A.Concurrent transactions don't see each other's uncommitted intermediate state — each transaction appears to execute as if it were the only one running
B.The database is protected against hardware failures and disk crashes
C.Each transaction is stored in its own isolated table namespace
D.Indexes remain consistent while transactions are in progress
Sign up free to take the full check and see the answer with an explanation.
What this module tests
- Conceptual understanding of transactions & concurrency fundamentals
- Trade-offs and design decisions in real system scenarios
- acid and transaction — applied knowledge
- Interview-style reasoning and explanation quality
Free to start
Take the Transactions & Concurrency check →
10 questions · Dimension scoring · AI coach feedback · Shareable result
Test your knowledge — free →No credit card · Takes 10–15 min
Frequently asked questions
- What does the Transactions & Concurrency check test?
- The check covers acid, isolation levels, dirty/phantom reads, deadlock prevention, select for update, optimistic locking. Questions span beginner to advanced difficulty and test both conceptual understanding and practical trade-off reasoning.
- What keywords should I know for Transactions & Concurrency?
- Key concepts include: acid, transaction, isolation, read committed, repeatable read, deadlock, select for update, optimistic locking. These frequently appear in sql & databases interviews at product and infrastructure companies.
- How many questions are in the check?
- Each check has 10 questions — a mix of MCQ and short-answer. You get scored by dimension (e.g., scalability, consistency) so you know exactly where to focus.
- How long does it take to study Transactions & Concurrency?
- Most engineers spend around 3 hours on this module. The check itself takes about 10–15 minutes. You can retake it up to 3 times per day.
- What prerequisite knowledge do I need before Transactions & Concurrency?
- Transactions & Concurrency builds on Schema Design & Normalization. Complete those first for the best results.
- Is acid, transaction, isolation covered?
- Yes. The Transactions & Concurrency module covers acid, transaction, isolation among other key concepts. The check includes questions that reflect real sql & databases interview patterns.