PDM Engineering Interview Questions and Answers

Optimising MongoDB Database involves indexing, proper query optimization, sharding, and using the right data model.

• Create indexes on fields frequently used in queries to improve query performance.

• Use the explain() method to analyze and optimize query performance.

• Implement sharding to distribute data across multiple servers for scalability.

• Use the appropriate data model for your application to reduce the number of queries needed.

• Regularly monitor and optimize the database perf...read more

Indexing in MongoDB improves query performance by allowing the database to quickly locate and retrieve specific documents.

• Indexes in MongoDB are similar to indexes in relational databases, allowing for efficient data retrieval.

• Types of indexes in MongoDB include single field, compound, multikey, text, hashed, and geospatial indexes.

• Single field indexes are created on a single field in a document, while compound indexes are created on multiple fields.

• Multikey indexes are used ...read more

Django ORM is used to interact with the database in a more Pythonic way, allowing developers to work with database tables as Python objects.

• Django ORM abstracts away the complexities of SQL queries, making it easier for developers to interact with the database.

• It provides an object-oriented interface to interact with the database, allowing developers to define models and perform CRUD operations.

• Django ORM automatically handles database transactions, migrations, and relationsh...read more

Media queries are CSS rules that allow for different styles to be applied based on the characteristics of the device displaying the webpage.

• Media queries are used in responsive web design to make websites adapt to different screen sizes and resolutions.

• They are written using the @media rule in CSS.

• Media queries can target various features such as screen width, height, orientation, and resolution.

• Example: @media only screen and (max-width: 600px) { /* styles for screens up to ...read more

Django follows the Model-View-Controller (MVC) architectural pattern, with models representing data, views handling user interface, and controllers managing the logic.

• Django uses the Model-View-Template (MVT) pattern, where templates handle the presentation layer.

• Models define the data structure, views handle user requests and responses, and templates render the HTML output.

• Django's architecture promotes reusability, modularity, and rapid development.

• The framework provides bu...read more

Binary search algorithm to find an element in a sorted array.

• Define a function that takes a sorted array and a target element as input.

• Initialize low and high pointers to the start and end of the array.

• While low pointer is less than or equal to high pointer, calculate mid pointer and compare target with element at mid.

• If target is found at mid, return mid index. If target is less than element at mid, update high pointer. If target is greater, update low pointer.

• Repeat until t...read more