SQL
Finding Records Without Related Data (Anti-Join)
Discover how to efficiently find records in one table that do not have a corresponding entry in another related table using an anti-join pattern.
SELECT p.id, p.name
FROM products p
LEFT JOIN orders o ON p.id = o.product_id
WHERE o.product_id IS NULL;
How it works: This query identifies records in the 'products' table that have no matching entry in the 'orders' table. It uses a `LEFT JOIN` to combine the tables, then filters for cases where the joined column from the right table ('orders') is `NULL`, indicating no match was found.