What are the different Types of Keys in Relational Model?
Tests knowledge of Primary, Foreign, Candidate, Super, and Alternate keys.
Why Interviewers Ask This
Keys define relationships and constraints. Interviewers assess your ability to design schemas that enforce referential integrity and uniqueness.
How to Answer This Question
List and define each key type. Explain how Primary Keys uniquely identify rows. Describe Foreign Keys linking tables. Mention Candidate Keys as potential primary keys. Use examples to illustrate relationships between entities.
Key Points to Cover
- Primary Key definition
- Foreign Key relationships
- Candidate vs Super keys
- Integrity enforcement
Sample Answer
In relational databases, keys include Primary Keys for unique identification, Foreign Keys for linking tables, and Candidate Keys as potential primary keys. Super Keys are any sets of attributes that uniquely identify a row, while Alternate Keys are candidate keys not chosen as primary. These ensure data integrity and efficient querying.
Common Mistakes to Avoid
- Confusing primary and foreign keys
- Omitting alternate keys
- Failing to explain uniqueness
Practice This Question with AI
Answer this question orally or via text and get instant AI-powered feedback on your response quality, structure, and delivery.
Related Interview Questions
What is ER model in the DBMS?
Medium
FlipkartWhat is database normalization and why is it important?
Medium
FlipkartWhat is the difference between LIKE and equals operators in SQL?
Easy
TCSWhat is the difference between DELETE and TRUNCATE commands in SQL?
Easy
FlipkartWhat is the difference between authentication and authorization?
Easy
FlipkartHow do you prioritize tasks when multiple deadlines are approaching?
Medium
Flipkart