What is ORM?

Object-Relational Mapping (ORM) is a technique that allows converting data between incompatible system types using an object-oriented language. Essentially, it is a "bridge" between object-oriented code (e.g., C#) and a relational database (e.g., SQL Server).

ORM providers for C#:

• Entity Framework (Core)
• NHibernate
• Dapper

Advantages of using ORM:

• Accelerates development: Reduces the amount of manual code writing for database interactions (CRUD operations).
• Database abstraction: Code becomes less dependent on a specific relational DBMS.
• Object-oriented: Data operations are performed through objects, which is more natural for object-oriented languages.
• Reduces errors: ORM can help prevent common SQL errors (e.g., SQL Injection, type mismatches).

Disadvantages:

• Learning curve: ORM has its own specifics and requires learning.
• Performance: In some complex scenarios, direct SQL may be more performant than ORM-generated queries.
• Over-abstraction: Sometimes, database abstraction can hinder debugging and query optimization.