Q1. What is CRUD, and why is it important?
CRUD represents Create, Read, Update, and Delete. It is important because it defines the basic operations required for data management in applications and ensures a structured way of interacting with databases and APIs.
Q2. How do CRUD operations map to SQL queries?
- Create → INSERT INTO table_name . . .
- Read → SELECT * FROM table_name . . .
- Update → UPDATE table_name SET . . .
- Delete → DELETE FROM table_name . . .
Q3. How are CRUD operations implemented in REST APIs?
CRUD maps to HTTP methods:
- Create → POST
- Read → GET
- Update → PUT or PATCH
- Delete → DELETE
Q4. What challenges can arise in CRUD operations, and how do you optimize them?
Common challenges include performance issues, data integrity, and concurrency conflicts. Optimizations involve using indexes, proper query design, transactions, caching, and implementing access control.
Q5. Can you explain CRUD in the context of ORM frameworks (like Hibernate or Sequelize)?
ORMs abstract CRUD operations into methods. For example, in Hibernate, session.save() performs Create, session.get() performs Read, session.update() performs Update, and session.delete() performs Delete. This makes database operations easier without writing raw SQL.