Primary vs Foreign Keys | Dataford Interview Questions

Explain the difference between a primary key and a foreign key in SQL.

Use the Airtel customer and subscription tables below to identify the key columns in each table and show how they relate.

Output

One row per key column in the schema
Columns: table_name, column_name, key_type, references_table, references_column
Include both primary keys and foreign keys, ordered by table_name, then key_type, then column_name

airtel_customers

airtel_subscriptions

Column	Type	Description
subscription_idPK	INT	Unique subscription identifier
customer_id	INT	Customer identifier referenced from airtel_customers
plan_name	VARCHAR(50)	Subscription plan name

Your question is Primary vs Foreign Keys. Start with the requirements and the two tables in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Explain the difference between a primary key and a foreign key in SQL.

Use the Airtel customer and subscription tables below to identify the key columns in each table and show how they relate.

One row per key column in the schema
Columns: table_name, column_name, key_type, references_table, references_column
Include both primary keys and foreign keys, ordered by table_name, then key_type, then column_name

airtel_customers

airtel_subscriptions

Column	Type	Description
subscription_idPK	INT	Unique subscription identifier
customer_id	INT	Customer identifier referenced from airtel_customers
plan_name	VARCHAR(50)	Subscription plan name

Your question is Primary vs Foreign Keys. Start with the requirements and the two tables in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.