What is the N+1 query problem in Node.js applications using an ORM like Mongoose or Sequelize?

Question

Node.js Developer — Hard

What is the N+1 query problem in Node.js applications using an ORM like Mongoose or Sequelize?

Accepted Answer

The N+1 query problem in Node.js applications using an ORM like Mongoose or Sequelize refers to fetching a list of N items with one query, then issuing an additional query for each item to retrieve related data. This results in N+1 total queries instead of using a join or populate, leading to performance issues.