Junior Application Developer Interview Questions and Answers

To fetch data from MongoDB, use the find() method with optional query parameters.

• Use the find() method to retrieve data from a MongoDB collection

• You can pass query parameters to filter the results

• Use the findOne() method to retrieve a single document

To upload a file to a server, you can use a form with a file input field or use a server-side script to handle the file upload process.

• Create a form with a file input field in HTML.

• Use a server-side script (e.g. PHP, Node.js) to handle the file upload process.

• Validate the file type and size before uploading.

• Move the uploaded file to a designated folder on the server.

• Provide feedback to the user after the file has been successfully uploaded.

Soft delete is a technique used to mark records as deleted without actually removing them from the database.

• Add a 'deleted_at' column to the database table to store the timestamp of when the record was soft deleted

• Update queries to set the 'deleted_at' timestamp when a record is soft deleted

• Modify queries to exclude soft deleted records by checking for 'deleted_at' column being null

Mongoose provides a schema-based solution for modeling data in MongoDB, making it easier to work with complex data structures.

• Mongoose simplifies interactions with MongoDB by providing a schema-based solution

• It allows for defining data models with validation rules and relationships between data

• Mongoose also provides middleware functions for pre and post processing of data operations

Middleware is software that acts as a bridge between different applications or components, allowing them to communicate and work together.

• Middleware facilitates communication between different software components

• It can handle tasks such as data transformation, security, and routing

• Examples include message brokers like RabbitMQ, API gateways like Kong, and web servers like Apache Tomcat