MySQL vs PostgreSQL for Java Developers

See full structured answer at https://interviewexplainer.com/postgresql-interview-questions/mysql-vs-postgresql-java-developers

PostgreSQL Window Functions — RANK, ROW_NUMBER, LAG, LEAD

See full structured answer at https://interviewexplainer.com/postgresql-interview-questions/postgresql-window-functions

PostgreSQL JSONB vs JSON — Operators, Indexing, Decision Tree

See full structured answer at https://interviewexplainer.com/postgresql-interview-questions/postgresql-jsonb-vs-json

PostgreSQL Indexes — B-Tree, GIN, GiST, BRIN, Hash

See full structured answer at https://interviewexplainer.com/postgresql-interview-questions/postgresql-indexes-btree-gin-gist

PostgreSQL Transaction Isolation Levels — Read Committed, Repeatable Read, Serializable

See full structured answer at https://interviewexplainer.com/postgresql-interview-questions/postgresql-transactions-isolation-levels

PostgreSQL Full-Text Search — tsvector, tsquery, GIN, Ranking

See full structured answer at https://interviewexplainer.com/postgresql-interview-questions/postgresql-full-text-search

PostgreSQL Connection Pooling with PgBouncer — Transaction vs Session Pooling

See full structured answer at https://interviewexplainer.com/postgresql-interview-questions/postgresql-connection-pooling-pgbouncer

Data & Persistence·Interview Q&A

PostgreSQL interview questions

12+ curated questions with the same answer shape every time: quick recap, deep dive, pitfalls, and follow-ups. Coverage includes postgresql features.

12questions

1topics

1110difficulty

Open question 1 How to read this module

Suggested path

Read PostgreSQL from question 1 to 12

Topics follow a teaching order. Each answer ends with a clear Next question control so you can move forward without hunting the list.

1Start with question 1 — it sets up the rest of the module.
2Use Continue · Next question at the bottom of every page (and the arrows in the sticky bar when you scroll).
3Jump to any topic in the full catalog — every row is numbered in reading order (Q1–Q12).

Open question 1 Jump to Q1 in list Scroll to full catalog

About this page

PostgreSQL is a single-topic module. This module covers PostgreSQL features — JSONB, CTEs, window functions, indexing (B-tree, GIN, GiST), EXPLAIN, partitioning, full-text search — organized as an elevation arc within the one topic from the fundamentals through to the advanced features that separate Postgres users from Postgres experts.

Reviewed by senior engineers·Updated for 2026·Free · No sign-up required

Part ofDatabases & Caching

High-signal PostgreSQL questions

Top 1

1Postgresql FeaturesPostgreSQL Fundamentals

Full catalog

Every question, in reading order

Topics are ordered for learning. Within each topic, rows are numbered 1–12 globally so you always know where you are. Collapse topics if you want a lighter view — use Expand all when you need the full list again.

Full catalog · reading order

PostgreSQL

Numbers 1–12 follow the order we recommend — click any row to open the full answer, or use the sticky Next link at the bottom of each page to go Q1 → Q12.

12 questions·1 topics

Continue your prep

Interviewers rarely ask PostgreSQL in isolation. These are the modules that most often come up in the same loop.

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FAQs about PostgreSQL interview prep

QHow many PostgreSQL interview questions are on this page?

This module bundles 12+ PostgreSQL interview questions, grouped by 1 topic. Every answer follows the same structure — one-liner summary, structured deep-dive, common pitfalls, and realistic follow-ups an interviewer might ask.

QIs this PostgreSQL content up to date for 2026?

Yes. Every answer is reviewed by senior engineers and updated for current best practices, version-specific APIs, and the scenario questions hiring managers are asking today.

QWhich difficulty level are these PostgreSQL questions?

The set spans all three levels — 1 easy, 11 medium, and 0 hard questions. Junior candidates should focus on the conceptual questions; senior candidates should drill the scenario and trade-off questions in every topic group.

QWhich question should I read first?

Start with question 1 in the ordered list below ("PostgreSQL Fundamentals") — it is the recommended entry point. Then use the Next question link at the bottom of each answer page to read straight through to Q12.

QWhat else belongs in a Databases & Caching prep plan?

PostgreSQL is one module inside the broader Databases & Caching hub — open it to drill the full set of sibling modules with the same structured answer format.