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.
How does Git mark merge conflicts in the affected files?
- Adding a "Conflict" label to conflicted lines
- Appending "-conflict" to file names
- Creating a separate conflicted branch
- Using special conflict markers (<<<<<<<, =======, >>>>>>>)
Git marks merge conflicts in the affected files using special conflict markers like <<<<<<<, =======, and >>>>>>>. These markers indicate the conflicting sections that need manual resolution.
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.
What does ACID stand for in the context of database transactions?
- Access, Control, Identification, Deletion
- Aggregation, Composition, Inheritance, Duplication
- Association, Collaboration, Integration, Deployment
- Atomicity, Consistency, Isolation, Durability
ACID stands for Atomicity, Consistency, Isolation, and Durability. These properties ensure the reliability and integrity of database transactions. Atomicity ensures that a transaction is treated as a single, indivisible unit of work. Consistency ensures that the database remains in a valid state before and after the transaction. Isolation prevents interference between concurrent transactions, and Durability ensures that the changes made by a committed transaction are permanent.
The term NoSQL refers to non-_______ databases.
- Relational
- SQL
- Structured
- Tabular
The term NoSQL refers to non-SQL databases. NoSQL databases are designed to handle unstructured or semi-structured data and provide flexibility in data storage and retrieval.