PostgreSQL Practice
Master PostgreSQL from your first query to production, with hands-on SQL, analytics, indexing, transactions, security, performance tuning and replication, all tested against a real database.
PostgreSQLData Types & Table Design
Pick the column types that enforce the rules: exact money, whole counts, bounded text, instants, enumerated states, defaults and database-generated keys.
Invoice Amounts That Drift
Times, Flags and States
Keys Nobody Has to Invent
Clinic Appointment Book
Constraints & Keys
Make the database enforce the rules: primary and unique keys, foreign keys with the right delete behaviour, named NOT NULL and CHECK rules, and rolling a rule out over legacy data.
Duplicate Customers
Orphaned Order Lines
Impossible Values Accepted
Event Ticketing Schema
Querying Fundamentals
Ask the database precise questions: range, list and pattern filters with grouped logic, null-aware predicates and fallbacks, stable ordering and paging, one row per group, and value banding.
Search That Ignores the Filters
The Missing Nulls
Pages Out of Order
Rental Listings Finder
Joins & Set Operations
Bring tables together without losing rows: inner, left and full outer joins through a junction table, self joins, anti-joins, cross joins, and reconciling two lists with set operations.
About this path
This path starts with the SQL foundations of PostgreSQL: data types and table design, constraints and keys, querying, and joins and set operations. It helps to know what tables and rows are, but no earlier PostgreSQL experience is needed. The joins module shows how to combine tables to answer questions a single table can't.
Frequently asked questions
4What will I practice in this path?
4 modules: Data Types & Table Design, Constraints & Keys, Querying Fundamentals and Joins & Set Operations.
How many challenges are there, and how hard are they?
12 challenges, all easy.
What does this path run on?
Challenges run on PostgreSQL.
Do I need to install anything?
No. Every challenge runs in a browser-based IDE with everything already set up, and your code is graded automatically against a test suite.