SQL Job Readiness

Resume snapshot

Skills: PostgreSQL 16, advanced SQL (CTEs, window functions, recursive queries), database design + normalization, indexing + EXPLAIN ANALYZE, transactions + isolation, JSONB + full-text search, Prisma + node-postgres, db migrations. Projects: pl-sql-passion repo + hosted Neon DB. Bonus: any dbt project, Kaggle SQL competition, contributed to a Postgres extension.

Interview questions

'Find the 2nd highest salary per department.' (Window function: DENSE_RANK or ROW_NUMBER.) 'Find users who haven't ordered in 30 days.' (LEFT JOIN + WHERE IS NULL or NOT EXISTS.) 'Difference between UNION and UNION ALL?' (UNION dedupes; UNION ALL doesn't.) 'Explain index B-tree.' 'When would you denormalize?' 'What's the N+1 query problem?' 'Walk through ACID.' 'Design a schema for [domain].' (Live whiteboarding, this is where pl-sql-passion shines.)

Portfolio + 60-day plan

Five concrete commitments.

1. 1

   1. Ship pl-sql-passion with hosted Neon + 15-query gallery + ER diagram.

2. 2

   2. Solve 30 LeetCode SQL problems (medium + hard). Free + employer-recognized.

3. 3

   3. Write a blog post: 'How I designed [your passion project domain]' walking through schema decisions.

4. 4

   4. (For data eng path) Build a dbt mini-project, even on top of pl-sql-passion.

5. 5

   5. (Optional cert) Coursera Google Data Analytics OR Postgres certification, both fine signals.

Common mistakes

Listing 'SQL' with no schema artifact. Knowing SELECT/JOIN but not CTEs / windows / indexes (the senior-level stuff). Not knowing your DB engine's specifics (Postgres vs MySQL vs SQL Server have important differences). Skipping the indexing + EXPLAIN section of every interview, the #1 SQL-perf topic.