The relationship between a department and an employee in a company database is typically _______.

  • Many-to-Many
  • Many-to-One
  • One-to-Many
  • One-to-One
The relationship between a department and an employee in a company database is typically a One-to-Many relationship. This indicates that one department can have multiple employees, but each employee belongs to only one department.

How does a graph database differ from other types of NoSQL databases?

  • It focuses on relationships between data points
  • It is optimized for high-speed transactions
  • It supports complex queries with SQL
  • It uses a tabular structure to store data
A graph database differs by focusing on relationships between data points. It utilizes nodes and edges to represent entities and their connections, making it particularly suitable for scenarios where understanding and querying relationships are crucial, such as social networks or fraud detection.

How does eventual consistency differ from strong consistency in NoSQL databases?

  • Data consistency is achieved over time and may not be immediate
  • Data consistency is achieved through strict synchronization
  • Data consistency is irrelevant in NoSQL databases
  • Data is immediately consistent across all nodes
Eventual consistency in NoSQL databases means that over time, all replicas of the data will converge to the same value, but it may not be immediately consistent. Strong consistency, on the other hand, ensures that all nodes have the same data at the same time.

What does the term "weak entity" refer to in an ERD?

  • An entity that depends on another entity for identification
  • An entity that does not have a unique identifier
  • An entity with a composite primary key
  • An entity without any attributes
In an ERD, a weak entity is one that does not have a unique identifier on its own and depends on another related entity for identification. It typically has a partial key, which is a set of attributes that, in combination with the parent entity's key, uniquely identifies instances of the weak entity.

Scenario: An e-commerce platform processes orders and handles inventory management. What steps would you implement to enforce data integrity in this system?

  • Allowing inconsistent data formats
  • Delayed data validation processes
  • Redundancy in data storage
  • Using unique identifiers for products and orders
Enforcing data integrity in an e-commerce platform involves using unique identifiers for products and orders. This ensures that each product and order is uniquely identified, preventing duplication and ensuring consistency. Redundancy, inconsistent data formats, and delayed validation processes can introduce errors and compromise data integrity.

Which schema typically results in simpler queries: Star Schema or Snowflake Schema?

  • Both have the same query complexity
  • Query complexity depends on data size
  • Snowflake Schema
  • Star Schema
Star Schemas typically result in simpler queries. The denormalized structure of a Star Schema, with a central Fact Table surrounded by Dimension Tables, reduces the number of joins needed in queries. This simplicity makes it easier for users to retrieve and analyze data without navigating through multiple normalized tables as in a Snowflake Schema.

Scenario: A financial institution requires immediate consistency across all its branches when updating account balances. Which consistency model would be most suitable for their NoSQL database?

  • Causal Consistency
  • Eventual Consistency
  • Session Consistency
  • Strong Consistency
Immediate consistency is crucial for a financial institution. Therefore, Strong Consistency is the most suitable model as it ensures that updates are instantly reflected across all branches without any delay or inconsistency.

Scenario: You are designing a social networking platform where users can follow other users and share posts. Which NoSQL database type would you choose and why?

  • Column-family Store
  • Document Store
  • Graph Database
  • Key-Value Store
For a social networking platform with complex relationships like followers and shared posts, a Graph Database would be suitable. Graph databases excel at handling relationships between entities, making it efficient to represent connections between users and their activities in this scenario.

Type 6 Slowly Changing Dimensions (SCD) combines features of Type 1, Type 2, and _______.

  • Type 3
  • Type 4
  • Type 5
  • Type 7
Type 6 SCD combines features of Type 1 (overwrite), Type 2 (preserve history), and Type 4 (maintain history in a separate table). This type is versatile and suits scenarios where a comprehensive history, including changes in both dimensions and attributes, is necessary.

What are some common strategies for implementing partitioning in a distributed database system?

  • Interval partitioning, Nested partitioning, Join partitioning, Broadcast partitioning
  • Range partitioning, Hash partitioning, List partitioning, Round-robin partitioning
  • Subpartitioning, Federation, Denormalization, Normalization
  • Vertical partitioning, Distributed partitioning, Sharding, Replication
Common strategies for implementing partitioning in a distributed database system include Range partitioning (dividing data based on ranges), Hash partitioning (using a hash function), List partitioning (based on a specified list of values), and Round-robin partitioning (equal distribution without specific criteria). These strategies aid in efficient data management and retrieval in a distributed environment.

Which symbol is used to represent a relationship between entities in an ERD?

  • Circle
  • Diamond
  • Rectangle
  • Triangle
In an ERD, a diamond-shaped symbol is used to represent a relationship between entities. This symbol indicates how entities are connected or related to each other in the database schema. The lines drawn between entities and the diamond symbolize the nature and cardinality of the relationship.

In Dimensional Modeling, what is a slowly changing dimension (SCD)?

  • A dimension that changes at a variable rate
  • A dimension that changes over time and requires historical tracking
  • A dimension that changes rapidly over time
  • A dimension that rarely changes
A slowly changing dimension (SCD) in Dimensional Modeling refers to a dimension that changes over time and requires historical tracking. It involves maintaining historical data for changes in dimension attributes to analyze trends and patterns over different points in time.