SQL Interview Questions & Practice

Sample SQL interview questions

• Joins Queries

  Can you explain the difference between an inner join and a left join, and give an example of when you'd need the left join specifically?

• Indexing

  Can you explain what a database index actually is, and why it speeds up reads but can slow down writes?

• Normalization

  Can you explain what normalization is, and walk me through the difference between first, second, and third normal form at a high level?

• Transactions Acid

  Can you explain what ACID stands for, and walk me through what each property actually guarantees?

• Performance Optimization

  How would you go about diagnosing why a specific query is slow?

• Schema Design

  How do you decide between storing a value as a column versus a separate related table?

• Nosql Vs Sql

  Can you explain the core tradeoff between a relational database and a document store like MongoDB?

• Concurrency Locking

  Can you explain the difference between optimistic and pessimistic locking, and when you'd use each?

These are a few examples — each real session pulls 5 questions at random from a larger pool across every category above, so repeat sessions won't repeat the same set.

Frequently asked questions

Is this a live-coding SQL interview?

No. SQL practice on Hone is a spoken, conceptual discussion — you explain your reasoning out loud rather than writing or sharing code.

How many SQL questions are there?

Each session pulls 5 questions at random from a larger pool across multiple categories, so repeat sessions don't repeat the same set.

Can I choose the difficulty?

Yes — easy, medium, or hard, chosen right before you start. It changes how hard the interviewer pushes on follow-ups and how strictly it scores your answers.

Is it free?

Yes — every account gets 5 interviews a month, any track, for free. Pro upgrades to unlimited interviews for $99/month.