Entity-Attribute-Value (EAV):?

Short answer: A flexible schema design used for scenarios where attributes of entities are dynamic and can vary over time. Example: A Product might have a variety of attributes like size, color, and weight, but some products may not have all attributes, so you store them as key-value pairs.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.