| 1 | What is Mongoose, and what does it add on top of the raw MongoDB Node.js driver? Node.js › Databases & ORMs (MongoDB/Mongoose, SQL/Sequelize) | Node.js | Databases & ORMs (MongoDB/Mongoose, SQL/Sequelize) | Beginner |
| 2 | How does Sequelize define models and relationships for a relational (SQL) database in Node.js? Node.js › Databases & ORMs (MongoDB/Mongoose, SQL/Sequelize) | Node.js | Databases & ORMs (MongoDB/Mongoose, SQL/Sequelize) | Intermediate |
| 3 | How do you implement database transactions in Node.js using Sequelize to ensure multiple related writes succeed or fail together? Node.js › Databases & ORMs (MongoDB/Mongoose, SQL/Sequelize) | Node.js | Databases & ORMs (MongoDB/Mongoose, SQL/Sequelize) | Intermediate |
| 4 | What is a database migration, and how do tools like Sequelize's migration system or a standalone tool like Knex help manage schema changes over time? Node.js › Databases & ORMs (MongoDB/Mongoose, SQL/Sequelize) | Node.js | Databases & ORMs (MongoDB/Mongoose, SQL/Sequelize) | Intermediate |
| 5 | What is the N+1 query problem in the context of an ORM like Mongoose or Sequelize, and how do you avoid it? Node.js › Databases & ORMs (MongoDB/Mongoose, SQL/Sequelize) | Node.js | Databases & ORMs (MongoDB/Mongoose, SQL/Sequelize) | Advanced |
| 6 | What is the difference between a relational (SQL) database and a NoSQL database, and how does this affect a Node.js application's data layer? Node.js › Databases | Node.js | Databases | Beginner |
| 7 | What is SQL injection, and how does using parameterized queries in Node.js prevent it? Node.js › Databases | Node.js | Databases | Intermediate |
| 8 | What is the N+1 query problem, and how does it commonly arise in a Node.js application using an ORM? Node.js › Databases | Node.js | Databases | Intermediate |
| 9 | What is the difference between a one-to-many and a many-to-many relationship in a relational database, and how is each modeled? Node.js › Databases | Node.js | Databases | Intermediate |
| 10 | What is a database transaction, and how would you implement one in Node.js to ensure multiple related writes either all succeed or all fail together? Node.js › Databases | Node.js | Databases | Advanced |