Which feature of Key-Value Stores makes them suitable for high-performance applications?

  • ACID transactions
  • Ability to scale horizontally
  • Complex querying capabilities
  • Strong data consistency guarantees
Key-Value Stores are suitable for high-performance applications due to their ability to scale horizontally. This means that they can handle large amounts of traffic and data by distributing the load across multiple servers or nodes. Horizontal scaling is essential for applications that require high throughput and low latency.

Scenario: A university has departments and professors. Each department can have multiple professors, and a professor can belong to only one department. How would you represent this scenario in an Entity-Relationship Diagram (ERD)?

  • Many-to-Many
  • Many-to-One
  • One-to-Many
  • One-to-One
In this scenario, a One-to-Many relationship would be appropriate. Each department can have multiple professors (One-to-Many), but a professor can belong to only one department. This reflects the constraint that each professor is associated with a single department.

How does a Key-Value Store differ from a traditional relational database?

  • Organizes data as key-value pairs without a fixed schema
  • Stores data in tables with predefined schema
  • Supports transactions and ACID properties
  • Utilizes complex join operations for querying
A Key-Value Store differs from a traditional relational database by organizing data as key-value pairs without a fixed schema. This provides flexibility, as each record can have different attributes without adhering to a predefined structure, making it suitable for scenarios with evolving or unpredictable data models.

_______ allows users to work on different versions of the data model simultaneously.

  • Branching
  • Locking
  • Merging
  • Versioning
Branching in version control allows users to work on different versions of the data model simultaneously. Each branch represents a separate line of development, enabling parallel work without interfering with the main model until changes are merged.

What does a document represent in document-based modeling?

  • A collection of related tables
  • A file in the file system
  • A row in a table
  • A self-contained piece of data in the database
In document-based modeling, a document represents a self-contained piece of data in the database. It is typically stored in a format like JSON and contains all the necessary information related to a specific entity or record, allowing for easy retrieval and manipulation.

In collaborative data modeling, _______ enables multiple users to work on the same model without conflicts.

  • Backup system
  • Encryption
  • Locking mechanism
  • Version control
In collaborative data modeling, version control allows multiple users to work on the same model concurrently. It helps manage changes, track revisions, and prevent conflicts by providing a systematic way to merge modifications from different contributors.

Scenario: A large e-commerce website needs to improve its search functionality by organizing product data more efficiently. How could clustering be applied to achieve this goal?

  • Categorizing products alphabetically
  • Creating indexes for each product
  • Grouping similar products together for faster retrieval
  • Sorting products by price
Clustering can be applied in e-commerce by grouping similar products together based on various features like product type, category, or user preferences. This grouping helps in organizing product data more efficiently, enabling faster search and retrieval processes for users.

What is the purpose of sharding in NoSQL databases?

  • To create indexes for faster query performance
  • To encrypt data for security purposes
  • To partition data horizontally across multiple nodes to improve scalability
  • To replicate data across multiple nodes for fault tolerance
Sharding in NoSQL databases involves horizontally partitioning data across multiple nodes to improve scalability. Each node (or shard) is responsible for a specific range of data, distributing the load and enabling the database to handle larger datasets and higher read/write throughput.

Scenario: An e-commerce platform needs to store product information, including images, descriptions, and pricing details. The platform wants to scale seamlessly as the number of products increases. Which database model would best suit this requirement and why?

  • Columnar Database
  • NoSQL Database
  • Object-Oriented Database
  • Relational Database
A NoSQL Database would be the best fit for this scenario. NoSQL databases, especially those designed for document storage, provide scalability and flexibility for handling diverse product information. The ability to store and retrieve complex data, including images and descriptions, aligns well with the requirements of an e-commerce platform.

In Dimensional Modeling, a _______ table contains descriptive attributes used for analysis.

  • Dimension
  • Fact
  • Lookup
  • Reference
In Dimensional Modeling, a Dimension table contains descriptive attributes used for analysis. These attributes provide context and additional information about the measures in the Fact table. For example, in a sales data warehouse, a Date Dimension table might contain attributes like year, quarter, and month.