Easy
SQL-J01sqlCustomers Who Placed Orders
Problem
Given `customers(id, name)` and `orders(id, customer_id, amount)`, return the **distinct names** of customers who placed at least one order, sorted alphabetically.
Input
Two tables: customers and orders.
Output
name (string)
Constraints
1 ≤ rows ≤ 10^5
Sample input
customers: (1,'Ada'), (2,'Linus'), (3,'Grace') orders: (10,1,99),(11,1,49),(12,3,12)
Sample output
Ada Grace
Explanation
Ada and Grace each have ≥1 order; Linus does not.
joinsinner-joindistinct@Amazon@Google
Visible test cases
in: see prompt
out: Ada Grace
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