SQL - Subqueries
Which of the following SQL queries correctly uses a JOIN to get all customers and their orders?
Which of the following SQL queries correctly uses a JOIN to get all customers and their orders?
easy📝 Syntax Q12 of 15
Step-by-Step Solution
Solution:
Step 1: Check JOIN syntax
Correct JOIN syntax uses ON with matching keys:customers.id = orders.customer_id.Step 2: Validate each option
SELECT customers.name, orders.id FROM customers JOIN orders ON customers.id = orders.customer_id; uses correct JOIN and ON condition. SELECT customers.name, orders.id FROM customers WHERE customers.id = orders.customer_id; uses WHERE without JOIN, which is invalid here. SELECT customers.name, orders.id FROM customers, orders WHERE customers.id == orders.customer_id; uses double equals (==) which is invalid in SQL. SELECT customers.name, orders.id FROM customers JOIN orders ON customers.customer_id = orders.id; reverses keys incorrectly.Final Answer:
SELECT customers.name, orders.id FROM customers JOIN orders ON customers.id = orders.customer_id; -> Option AQuick Check:
Correct JOIN syntax = SELECT customers.name, orders.id FROM customers JOIN orders ON customers.id = orders.customer_id; [OK]
Quick Trick: JOIN uses ON with matching keys, not WHERE or == [OK]
Common Mistakes:
MISTAKES- Using WHERE instead of ON for JOIN condition
- Using == instead of = in SQL
- Mixing up key columns in ON clause
Master "Subqueries" in SQL
Want More Practice?
15+ quiz questions · All difficulty levels · Free
Free Signup - Practice All QuestionsMore SQL Quizzes