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What SQL query should be written to list all users who did not place an order throughout the year?
sobes.tech AI
Answer from AI
Suppose there are two tables: users (with a user_id field) and orders (with user_id and order_date fields). You need to list all users who did not place any orders throughout the year (for example, 2023).
Example SQL query:
SELECT u.*
FROM users u
LEFT JOIN orders o ON u.user_id = o.user_id
AND o.order_date BETWEEN '2023-01-01' AND '2023-12-31'
WHERE o.user_id IS NULL;
Logic:
- The LEFT JOIN connects users with their orders for the specified year.
- The condition
WHERE o.user_id IS NULLselects only those users who have no orders in this period.
Thus, the query returns all users without orders for the entire year.