Glossary · Database

ORM

Object-Relational Mapping–a technique that lets developers interact with databases using programming language objects instead of SQL.

An ORM (Object-Relational Mapper) is a programming technique and toolset that creates a bridge between object-oriented programming languages and relational databases. Instead of writing raw SQL, developers define data models as classes and interact with the database through methods and properties. The ORM translates these object operations into SQL queries behind the scenes. Popular ORMs include SQLAlchemy (Python), Prisma and Sequelize (JavaScript/TypeScript), Hibernate (Java), Entity Framework (.NET), and ActiveRecord (Ruby). While ORMs improve developer productivity and reduce SQL injection risks, they can generate suboptimal queries for complex operations–a problem known as the "N+1 query problem."

Fig — every answer ships with the tables, rows and SQL behind it.