When resolving conflicts in Git, the modified files must be _______ before committing.
- Committed
- Merged
- Reverted
- Staged
When resolving conflicts in Git, the modified files must be staged (using "git add") after resolving the conflict but before committing the changes. Staging indicates that the conflicts have been addressed and are ready to be included in the next commit.
You're designing a high-traffic e-commerce website. What caching strategies would you implement to ensure optimal performance during peak times?
- Browser caching for static assets
- Content Delivery Network (CDN) caching
- Database caching
- In-memory caching with tools like Redis
In high-traffic e-commerce websites, in-memory caching with tools like Redis is crucial. It helps store frequently accessed data in memory, reducing the need to query the database repeatedly, and thus improving performance during peak times.
Which SQL keyword is used to retrieve data from a database?
- FETCH
- GET
- RETRIEVE
- SELECT
The SQL keyword used to retrieve data from a database is SELECT. It is the fundamental command to fetch data from one or more tables.
What is a Dockerfile used for in Docker containerization?
- Configuring network settings
- Defining the instructions to build a Docker image
- Managing multiple containers as a single application
- Storing runtime data of a container
A Dockerfile in Docker containerization is used to define the instructions needed to build a Docker image. It contains a set of commands that describe the base image, application code, dependencies, and configuration, allowing for consistent and reproducible image builds.
What are some strategies for handling asynchronous errors in Node.js?
- Caching, Authentication, Authorization, Rate Limiting
- Callbacks, Promises, Async/Await, Event Emitters
- Exception Handling, Error Codes, Logging, Retry Mechanism
- Polling, WebSockets, Threading, Buffers
Handling asynchronous errors in Node.js involves using strategies such as Callbacks, Promises, Async/Await, and Event Emitters. These mechanisms help in dealing with asynchronous code execution and managing errors effectively.
In a large-scale software project, how would you apply the SOLID principles to ensure maintainability and scalability?
- Interface Segregation Principle (ISP) for encapsulation
- Liskov Substitution Principle (LSP) for interoperability
- Open/Closed Principle (OCP) for extensibility
- Single Responsibility Principle (SRP) for modular functions
Applying SOLID principles involves using SRP for modular functions, OCP for extensibility, LSP for interoperability, and ISP for encapsulation. This ensures maintainability and scalability in a large-scale project.
The Python module used for logging is called _______.
- log
- logger
- logging
- record
The Python module used for logging is called logging. It provides flexible logging of messages and is a built-in module in Python for handling log messages from applications.
Explain the concept of cache coherency in distributed caching systems.
- Ensures that all nodes in the system have consistent data
- Maximizes cache size in a single node
- Minimizes the use of caching in distributed systems
- Prioritizes caching in specific nodes
Cache coherency in distributed systems ensures that all nodes have consistent data by synchronizing their caches. It prevents data inconsistencies across the network.
What is a deadlock in the context of concurrency control?
- A state where a database is locked for maintenance
- A state where a transaction is unable to acquire the necessary locks to proceed
- A state where transactions are executed in parallel without conflicts
- A state where two or more transactions are waiting indefinitely for each other to release locks
A deadlock occurs when two or more transactions are waiting indefinitely for each other to release locks, leading to a situation where none of the transactions can proceed. Deadlocks must be resolved to allow the system to continue processing transactions.
In Git, a "conflict" occurs when the changes in two branches are _______.
- Identical
- Incompatible
- Independent
- Synchronized
In Git, a "conflict" occurs when the changes in two branches are Incompatible. This happens when Git can't automatically merge changes due to conflicting modifications in the same lines of code. Resolving conflicts is necessary before completing the merge or rebase.