Write a SQL query that returns each customer ID and the total number of orders they placed in the year 2025, but only for customers who placed more than five orders.

You can achieve this with a simple GROUP BY and HAVING clause. Assuming the table is named Orders and has columns customer_id and order_date, the query would be:

SELECT customer_id,

   COUNT(*) AS total_orders

FROM Orders

WHERE YEAR(order_date) = 2025

GROUP BY customer_id

HAVING COUNT(*) > 5;

This counts all rows per customer for 2025, then filters out those with five or fewer orders. The complexity is O(n) where n is the number of rows in the Orders table. If the database supports DATE_TRUNC or similar functions, you could replace YEAR(order_date) with DATE_TRUNC('year', order_date) = DATE '2025-01-01' for better portability.