What will happen if you try to destructure properties not present in the object?

  • The properties will be assigned undefined, and no error will be thrown.
  • It will throw a "Property not found" error.
  • The properties will be ignored, and no action will be taken.
  • The code will fail to compile.
When destructuring properties not present in the object, they will be assigned undefined, and no error will be thrown. This is useful for handling optional properties or providing default values.

Pug was formerly known as ______ before it was renamed.

  • Jade
  • Twig
  • Slim
  • Haml
Pug was previously known as "Jade" before it was renamed due to a trademark issue. The other options are different templating engines and not related to Pug.

In a distributed database system, achieving ______ can be challenging during CRUD operations due to network partitions.

  • Consistency
  • Availability
  • Partition Tolerance
  • Latency
In a distributed database system, the CAP theorem states that you can achieve only two out of three properties: Consistency, Availability, and Partition Tolerance (CAP). During network partitions (Partition Tolerance), it can be challenging to maintain both Consistency and Availability, making it an essential trade-off.

You are designing a large-scale e-commerce platform that requires fast and accurate search functionality. What indexing and search strategies would you employ to ensure that users can find products efficiently and accurately?

  • Implement Inverted Indexes and Use Distributed Search Engines
  • Implement Relational Database Indexes Only
  • Utilize Full-Text Search Indexing for Product Descriptions
  • Employ In-Memory Caching for Frequent Queries
To ensure fast and accurate search functionality in a large-scale e-commerce platform, employing Inverted Indexes and Distributed Search Engines is a common strategy. These technologies allow for efficient and scalable search operations, as they pre-process and index the data in a way that speeds up retrieval. Full-Text Search Indexing is useful for searching within product descriptions. In-memory caching can further enhance query performance by storing frequently accessed data in memory. However, it's not a substitute for proper indexing and search strategies.

In Node.js, to interact with SQL databases, an ORM like ______ can be used.

  • Sequelize
  • MongoDB
  • Express
  • Mongoose
In Node.js, Sequelize is a popular Object-Relational Mapping (ORM) library used to interact with SQL databases. It provides an abstraction layer for working with databases, making it easier to manage and query relational data. Options 2, 3, and 4 are not ORMs and are not used for SQL databases.

In E2E testing, tests are executed in an environment that simulates a ________ user environment.

  • production
  • controlled
  • real
  • isolated
In End-to-End (E2E) testing, tests are executed in an environment that simulates a real user environment. This means the tests mimic the actions and interactions of real users with the application, helping ensure that the application works as expected in a production-like setting. While controlled and isolated environments may be used in testing, they are not the primary focus of E2E testing. Production environments are typically not used for testing to avoid risks to the live system.

You are developing a real-time chat application in Node.js. How would you design the application to handle a high number of simultaneous connections without degrading performance, considering the nature of the Event Loop and Non-Blocking I/O?

  • Use worker threads to offload CPU-intensive tasks.
  • Utilize Node.js cluster module for load balancing.
  • Implement microservices architecture for scalability.
  • Increase the Event Loop's thread pool size.
To handle a high number of simultaneous connections without degrading performance in Node.js, you can use the cluster module, which allows you to create multiple child processes (workers) to distribute the load efficiently. Options a and c do not directly address the Node.js Event Loop's nature, and option d is not a recommended approach as it may lead to thread contention.

You are developing a high-traffic RESTful API with Express. How would you design the architecture to ensure optimal performance, scalability, and maintainability?

  • Use a single server instance for simplicity.
  • Implement a microservices architecture with multiple small services.
  • Rely solely on client-side caching to reduce server load.
  • Don't worry about code structure; focus on hardware upgrades for scalability.
Implementing a microservices architecture with multiple small services allows for optimal performance, scalability, and maintainability. Using a single server instance can become a bottleneck in high-traffic scenarios. Relying solely on client-side caching doesn't address server-side performance and scalability issues. Neglecting code structure and relying on hardware upgrades is not a best practice for maintainability.

How can composite indexing be optimized to enhance query performance in relational databases?

  • Use covering indexes
  • Increase the number of indexed columns
  • Avoid indexing on frequently updated columns
  • Use B-tree indexes only
Composite indexing can be optimized by using covering indexes, which include all the columns required by a query. This reduces the need for additional table lookups and can significantly enhance query performance. Increasing the number of indexed columns may not always be beneficial as it can increase index maintenance overhead. Indexing frequently updated columns should be avoided to prevent write performance degradation. B-tree indexes are just one type of composite index, and the choice of index type depends on the specific use case.

What is the significance of the tilde (~) symbol in a version number, like ~1.2.3, in semantic versioning?

  • It allows upgrades to the specified version and any future versions, including breaking changes.
  • It signifies that downgrades are allowed.
  • It restricts upgrades to only the specified version.
  • It allows upgrades to the specified version and any future backward-compatible versions.
The tilde (~) symbol allows upgrades to the specified version and any future backward-compatible versions while keeping you within the same major version. It's more restrictive than the caret (^).