Code Typing · SQL
Recursive CTE
Walk a category tree from the root down.
Difficulty: Advanced · 11 Lines · License: public-domain
WITH RECURSIVE category_tree AS (
SELECT id, name, parent_id, 0 AS depth
FROM categories
WHERE parent_id IS NULL
UNION ALL
SELECT c.id, c.name, c.parent_id, t.depth + 1
FROM categories AS c
INNER JOIN category_tree AS t
ON c.parent_id = t.id
Time0:00
Speed (WPM)0.0
Accuracy100.0%
Mistakes0
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