_______ 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.
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.
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.
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.
What are the potential disadvantages of normalizing a database too aggressively?
- Improved data integrity
- Increased complexity in query formulation and execution
- Reduced storage space requirements
- Simplified database maintenance
Aggressively normalizing a database may lead to increased complexity in query formulation and execution. While normalization enhances data integrity, it can make queries more intricate, impacting performance.
Scenario: A software development company utilizes cloud-based databases for its applications. However, they encounter storage cost issues due to excessive data redundancy. How can they address this challenge using storage optimization techniques?
- Implementing data deduplication
- Increasing data replication
- Reducing database indexing
- Utilizing larger storage capacity
To address storage cost issues caused by excessive data redundancy, the software development company can implement data deduplication. This technique involves identifying and eliminating duplicate data, leading to more efficient storage utilization and cost savings.
In database partitioning, what does range partitioning involve?
- Dividing data based on alphabetical order
- Dividing data based on specified ranges of values
- Dividing data based on the number of rows
- Dividing data randomly
Range partitioning involves dividing data based on specified ranges of values. This is useful for scenarios where data is logically ordered, such as by date or numeric range. It helps in optimizing queries by narrowing down the search space within each partition.
Scenario: A social media platform needs to ensure that all users see the most recent posts made by their friends. Which consistency model would you recommend for their NoSQL database?
- Bounded Staleness
- Causal Consistency
- Eventual Consistency
- Strong Consistency
For a social media platform prioritizing consistency, Strong Consistency is recommended. This ensures that all users see the most recent posts made by their friends without any delay or inconsistency across different nodes of the database.
Scenario: An online store has customers and orders. Each customer can place multiple orders, but an order must belong to one customer. What cardinality and modality does this scenario illustrate?
- Many-to-Many, Optional
- Many-to-One, Optional
- One-to-Many, Mandatory
- One-to-One, Mandatory
This scenario illustrates a One-to-Many relationship with mandatory modality. Each customer can place multiple orders (Many), but each order must belong to one customer (One). The modality is mandatory because every order must be associated with a customer.
In a distributed database system, _______ partitioning involves replicating data across multiple nodes.
- Hash
- Range
- Replication
- Vertical
In a distributed database system, replication partitioning involves copying or duplicating data across multiple nodes. This is done to enhance fault tolerance and improve data availability by having redundant copies of the data on different nodes within the distributed environment.