What is a Fact Table in Dimensional Modeling?

  • A table that connects dimensions
  • A table that stores descriptive attributes
  • A table that stores historical data
  • A table that stores quantitative, measurable facts
In Dimensional Modeling, a Fact Table stores quantitative, measurable facts about a business process or event. It typically contains foreign keys that reference dimension tables for context.

Which data cleansing technique involves filling in missing values in a dataset based on statistical methods?

  • Deduplication
  • Imputation
  • Standardization
  • Tokenization
Imputation is a data cleansing technique that involves filling in missing values in a dataset based on statistical methods such as mean, median, or mode imputation. It helps maintain data integrity and completeness by replacing missing values with estimated values derived from the remaining data. Imputation is commonly used in various domains, including data analysis, machine learning, and business intelligence, to handle missing data effectively and minimize its impact on downstream processes.

Scenario: You are working on a project where data quality is paramount. How would you determine the effectiveness of the data cleansing process?

  • Compare data quality metrics before and after cleansing
  • Conduct data profiling and outlier detection
  • Measure data completeness, accuracy, consistency, and timeliness
  • Solicit feedback from stakeholders
Determining the effectiveness of the data cleansing process involves measuring various data quality metrics such as completeness, accuracy, consistency, and timeliness. Comparing data quality metrics before and after cleansing helps assess the impact of cleansing activities on data quality improvement. Data profiling and outlier detection identify anomalies and discrepancies in the data. Soliciting feedback from stakeholders provides insights into their satisfaction with the data quality improvements.

The ________ aspect of a data governance framework refers to the establishment of roles, responsibilities, and decision-making processes.

  • Organizational
  • Procedural
  • Structural
  • Technical
The procedural aspect of a data governance framework focuses on defining the processes, procedures, and workflows for managing data within an organization. This includes establishing roles and responsibilities, defining decision-making processes, and outlining procedures for data quality management, data security, and compliance. A robust procedural framework ensures that data governance policies are implemented effectively, leading to improved data quality, consistency, and reliability.

________ is a pattern that temporarily blocks access to a service experiencing a failure, allowing it to recover.

  • Circuit Breaker
  • Load Balancing
  • Rate Limiting
  • Redundancy
The Circuit Breaker pattern is a fault-tolerant design pattern used to manage failures in distributed systems. It temporarily blocks access to a service experiencing a failure, preventing cascading failures and allowing the service to recover. By detecting and isolating faulty components, the Circuit Breaker pattern promotes system stability and resilience, improving overall reliability and performance.

Scenario: You are designing an ERD for an online shopping platform. Each product can belong to multiple categories, and each category can have multiple products. What type of relationship would you represent between the "Product" and "Category" entities?

  • Many-to-Many
  • Many-to-One
  • One-to-Many
  • One-to-One
The relationship between "Product" and "Category" entities in this scenario is Many-to-Many, as each product can belong to multiple categories, and each category can have multiple products, forming a many-to-many relationship.

What distinguishes Apache ORC (Optimized Row Columnar) file format from other file formats in big data storage solutions?

  • Columnar storage and optimization
  • In-memory caching
  • NoSQL data model
  • Row-based compression techniques
Apache ORC (Optimized Row Columnar) file format stands out in big data storage solutions due to its columnar storage approach, which organizes data by column rather than by row. This enables efficient compression and encoding techniques tailored to columnar data, leading to improved query performance and reduced storage footprint. Unlike row-based formats, ORC allows for selective column reads, enhancing query speed for analytical workloads commonly found in big data environments.

Denormalization involves combining tables to ________ redundancy and improve ________.

  • Decrease, data consistency
  • Decrease, query performance
  • Increase, data consistency
  • Increase, query performance
Denormalization involves combining tables to increase query performance by reducing the need for joins, which can be resource-intensive. However, this may lead to data redundancy and decreased data consistency.

Scenario: Your team is dealing with a high volume of data that needs to be extracted from various sources. How would you design a scalable data extraction solution to handle the data volume effectively?

  • Centralized extraction architectures, batch processing frameworks, data silo integration, data replication mechanisms
  • Incremental extraction methods, data compression algorithms, data sharding techniques, data federation approaches
  • Parallel processing, distributed computing, data partitioning strategies, load balancing
  • Real-time extraction pipelines, stream processing systems, event-driven architectures, in-memory data grids
To design a scalable data extraction solution for handling high data volumes effectively, techniques such as parallel processing, distributed computing, data partitioning strategies, and load balancing should be employed. These approaches enable efficient extraction, processing, and management of large datasets across various sources, ensuring scalability and performance.

The use of ________ can optimize ETL processes by reducing the physical storage required for data.

  • Data compression
  • Data encryption
  • Data normalization
  • Data replication
The use of data compression can optimize ETL (Extract, Transform, Load) processes by reducing the physical storage required for data. It involves encoding data in a more compact format, thereby reducing the amount of disk space needed to store it.

What role does data stewardship play in a data governance framework?

  • Ensuring data compliance with legal regulations
  • Managing data access permissions
  • Overseeing data quality and consistency
  • Representing business interests in data management
Data stewardship involves overseeing data quality and consistency within a data governance framework. Data stewards are responsible for defining and enforcing data standards, resolving data-related issues, and advocating for the proper use and management of data assets across the organization.

What does a physical data model include that the other two models (conceptual and logical) do not?

  • Business rules and constraints
  • Entity-relationship diagrams
  • High-level data requirements
  • Storage structures and access methods
A physical data model includes storage structures and access methods, specifying how data will be stored and accessed in the underlying database system, which the conceptual and logical models do not.