You are designing a system with a high read/write ratio, requiring efficient database interactions. How would you configure Sequelize or Mongoose to minimize database load and optimize performance?
- Implement caching mechanisms.
- Use Sequelize's "findOneAndUpdate" method.
- Disable indexing on database columns.
- Increase the database connection pool size.
To optimize performance with a high read/write ratio, implementing caching mechanisms is a common strategy. Options 2, 3, and 4 are not recommended for this purpose. "findOneAndUpdate" is not related to optimizing read/write efficiency. Disabling indexing can harm performance, and increasing the connection pool size alone won't optimize database interactions.
In order to secure user passwords, it is best practice to store them using a ________ algorithm.
- Hashing
- Encryption
- Decryption
- Salting
To secure user passwords, it's best practice to store them using a hashing algorithm. Hashing takes the password and transforms it into a fixed-size string of characters (hash) using a one-way function. This makes it difficult to reverse-engineer the password from the stored hash.
What is the primary use of the Events module in Node.js?
- Managing file operations
- Handling asynchronous code
- Handling events and event-driven programming
- Defining custom data types
The primary use of the Events module in Node.js is to facilitate event-driven programming. It allows you to create, emit, and handle custom events, making it a fundamental part of building real-time and responsive applications. Options A, B, and D are not the primary purposes of the Events module.
In what scenario would you need to create a custom error class in Express.js?
- When you want to replace the built-in error classes
- When you want to provide additional metadata with the error
- When you need to handle synchronous errors
- When you want to suppress errors and continue execution
Creating a custom error class in Express.js is useful when you want to provide additional metadata with the error, such as error codes, status codes, or custom properties. This allows you to convey more context about the error to the client or developer. The other options are not typical use cases for custom error classes.
Which of the following scenarios is most suitable for incrementing the 'minor' version in semantic versioning?
- Adding new features or functionality in a backward-compatible manner.
- Fixing a critical security vulnerability that requires code changes.
- Refactoring the internal code structure without affecting external interfaces.
- Removing a public API that is no longer needed.
In semantic versioning, the 'minor' version should be incremented when new features or functionality are added in a backward-compatible manner. This indicates to users that they can safely update to the new version without worrying about breaking changes.
What is the significance of the process.nextTick() method in Node.js?
- It schedules a callback function to be executed in the next iteration of the event loop, immediately after the current operation is complete.
- It delays the execution of a callback function for a specific number of milliseconds.
- It cancels the execution of a callback function.
- It executes the callback function asynchronously in a new Node.js process.
process.nextTick() is used to schedule a callback function to be executed in the next iteration of the event loop, immediately after the current operation is complete. This allows for efficient asynchronous code execution. The other options do not accurately describe the purpose of process.nextTick().
You are designing a schema for a database that needs to support real-time analytics. What factors would you consider to optimize the read performance of the database?
- Indexing relevant columns for faster retrieval.
- Implementing caching mechanisms to reduce database load.
- Using NoSQL databases for flexibility.
- Denormalizing data for quicker query performance.
When designing a schema for real-time analytics, indexing relevant columns is crucial as it speeds up data retrieval. Option (2) is also valid, as caching can significantly reduce database load. Option (3) might be a consideration but isn't the primary factor. Option (4) can be a trade-off, and it depends on the specific use case.
How can you access the properties of an object in JavaScript?
- object.property
- object.getProperty()
- object.getProperty
- getProperty(object)
To access the properties of an object in JavaScript, you use dot notation like object.property. This is the most common and straightforward way to access object properties. The other options are not standard ways to access object properties.
To optimize write-intensive workloads in a database, it's crucial to minimize the use of ________.
- Indexes
- Locks
- Transactions
- Constraints
To optimize write-intensive workloads in a database, it's crucial to minimize the use of "Locks." Locks can lead to contention and slow down write operations, especially in scenarios with high concurrent writes.
The Buffer.isBuffer(obj) method in Node.js is used to determine if an object is a ______.
- string
- buffer
- stream
- file
The Buffer.isBuffer method is used to determine if an object is a buffer in Node.js. It helps identify whether a given object is a Buffer instance or not.