Design a polymorphic comments system
A medium Data Modeling mock interview question on DataDriven. Practice with AI-powered feedback, real code execution, and a hire/no-hire decision.
- Domain
- Data Modeling
- Difficulty
- medium
Interview Prompt
Design a polymorphic comments system. Instead of separate comment tables per entity, create one comments table that can reference either posts or photos using a commentable_type and commentable_id pattern.
How This Interview Works
- Read the vague prompt (just like a real interview)
- Ask clarifying questions to the AI interviewer
- Write your data modeling solution with real code execution
- Get instant feedback and a hire/no-hire decision