chapter 4

Question 1

What is ORM in the backend?

Answer 1

ORM means Object-Relational Mapping. It helps to work with SQL databases by converting tables into objects in your code.

Question 2

What is ODM in the backend?

Answer 2

ODM means Object-Document Mapping. It helps to work with NoSQL databases (like MongoDB) by converting documents into objects in your code.

Question 3

What is the main difference between ORM and ODM?

Answer 3

ORM is for SQL databases (tables, rows, columns).

ODM is for NoSQL databases (documents, collections).

Question 4

Give examples of ORM libraries.

Answer 4

Sequelize (Node.js), SQLAlchemy (Python), Hibernate (Java).

Question 5

Give examples of ODM libraries.

Answer 5

Mongoose (Node.js), MongoEngine (Python).

Question 6

Why use ORM or ODM?

Answer 6

To avoid writing raw SQL/NoSQL queries. You can work with objects directly in your code, which saves time and reduces errors.