SQL newest row per category

Select the most recently created row in each category using a window function.

Original Pearto instructional example. Test it in your own environment and adapt it to your requirements.

WITH ranked AS (
  SELECT id, category, created_at,
    ROW_NUMBER() OVER (PARTITION BY category ORDER BY created_at DESC, id DESC) AS rn
  FROM resources
)
SELECT id, category, created_at FROM ranked WHERE rn=1;