Advanced PostgreSQL Operations

Expert-level PostgreSQL patterns for production systems: analytical queries, JSON handling, search optimization, and performance tuning.

Window Functions

Perform calculations across row sets without collapsing results.

BAD: Self-join for ranking

-- Inefficient, creates cartesian product
SELECT e1.name, e1.salary, COUNT(e2.salary) as rank
FROM employees e1
LEFT JOIN employees e2 ON e1.salary <= e2.salary
GROUP BY e1.name, e1.salary;