In database modeling, a _______ key is a key that uniquely identifies a record within a table.

  • Composite
  • Foreign
  • Primary
  • Secondary
In database modeling, a primary key is a key that uniquely identifies a record within a table. It serves as the unique identifier for each row and ensures data integrity by preventing duplicate or null values in this key field.

What are the key considerations when designing a conceptual schema?

  • Data integrity, simplicity, and normalization
  • Data redundancy, complexity, and denormalization
  • Normalization, redundancy, and write efficiency
  • Query performance, redundancy, and complexity
Key considerations when designing a conceptual schema include maintaining data integrity, ensuring simplicity, and applying normalization techniques. These factors contribute to a robust and efficient database design.

What is the difference between functional dependency and multi-valued dependency?

  • Functional dependency and multi-valued dependency are terms used interchangeably to describe the same concept.
  • Functional dependency captures the relationship between attributes within a single table, ensuring unique determinants for other attributes. Multi-valued dependency, on the other hand, deals with situations where one attribute uniquely determines another, but multiple values can exist for the same determinant.
  • Functional dependency only applies to numeric attributes, while multi-valued dependency is exclusive to alphanumeric attributes.
  • Functional dependency signifies a one-to-one relationship, while multi-valued dependency implies a many-to-many relationship.
Functional dependency and multi-valued dependency are distinct concepts. Functional dependency deals with one-to-one relationships within a table, whereas multi-valued dependency handles situations where one attribute uniquely determines another, allowing for multiple values for the same determinant.

One key feature of document-based databases is _______ consistency, which allows for efficient distributed data management.

  • Causal
  • Eventual
  • Immediate
  • Strong
One key feature of document-based databases is eventual consistency. This consistency model prioritizes availability and partition tolerance in distributed systems, ensuring that all nodes eventually reach a consistent state despite potential network delays or failures. This makes document-based databases efficient for distributed data management in scenarios where real-time consistency is not a strict requirement.

Partitioning based on _______ involves dividing data based on specific ranges of values.

  • Attributes
  • Columns
  • Entities
  • Relationships
Partitioning based on Attributes involves dividing data based on specific ranges of values. This technique is commonly used to organize and manage large datasets efficiently, improving query performance and data retrieval.

_______ is the process of distributing data across multiple servers in a NoSQL database.

  • Data Aggregation
  • Data Fragmentation
  • Data Replication
  • Data Sharding
Sharding is the process of distributing data across multiple servers in a NoSQL database. It helps in improving performance and scalability by dividing the dataset into smaller, manageable parts that can be processed independently.

What does data integrity ensure in a database system?

  • Consistency of data
  • Data availability
  • Data confidentiality
  • Data speed
Data integrity in a database system ensures the consistency of data, meaning that the data is accurate, valid, and reliable throughout its lifecycle. It prevents inconsistencies and errors in the database.

The process of organizing data into multiple related tables while eliminating data redundancy is known as _______.

  • Aggregation
  • Denormalization
  • Indexing
  • Normalization
The process of organizing data into multiple related tables while eliminating data redundancy is known as normalization. Normalization is crucial for maintaining data integrity and reducing data anomalies in a relational database.

What is a key difference between Forward Engineering and Reverse Engineering in database management?

  • Forward Engineering focuses on optimizing query performance, while Reverse Engineering focuses on data validation.
  • Forward Engineering generates a database schema from a conceptual model, while Reverse Engineering does the opposite.
  • Forward Engineering is used for modifying existing database structures, while Reverse Engineering is used for creating new structures.
  • There is no difference; the terms are used interchangeably.
A key difference is that Forward Engineering involves generating a database schema from a conceptual model, moving from high-level design to implementation. In contrast, Reverse Engineering does the opposite, analyzing existing code or structures to create a conceptual model.

Scenario: A company has employees who are categorized into full-time and part-time workers. How would you represent this scenario using Generalization and Specialization?

  • Full-time and part-time workers as attributes of the employee entity
  • Full-time and part-time workers as separate entities
  • Full-time workers inheriting attributes from part-time workers
  • Part-time workers as a subtype of full-time workers
In this scenario, representing full-time and part-time workers as separate entities using Generalization and Specialization is the appropriate approach. Each entity can have its own set of attributes and behaviors, allowing for clear modeling and differentiation between the two types of employees.

Effective collaboration in data modeling requires clear _______ among team members.

  • Algorithms
  • Coding skills
  • Communication
  • Data structures
Clear communication is crucial for effective collaboration in data modeling. It ensures that team members understand each other's perspectives, requirements, and decisions, promoting a cohesive and efficient modeling process.

What strategies can be employed for handling changing dimensions in Dimensional Modeling?

  • Adding new records with new keys
  • All of the above
  • Creating separate tables for historical data
  • Overwriting existing data
Various strategies can be employed for handling changing dimensions, including overwriting existing data, adding new records with new keys, and creating separate tables for historical data. The choice depends on the specific requirements of the business and the nature of the dimension changes.