PostgreSQL

PostgreSQL CASE

Return different values based on conditions.

Use CASE

SELECT name, year,
  CASE
    WHEN year >= 2025 THEN 'New'
    WHEN year >= 2020 THEN 'Recent'
    ELSE 'Older'
  END AS age_group
FROM products;

PostgreSQL tests WHEN conditions in order and returns the first matching result. ELSE handles rows that match no condition.