Introduction to Distributed Databases

What defines a distributed database system?

Limited to one system
Spread over different sites (correct)
Managed by a single user
Located on a single site

What is a characteristic of a homogeneous database?

Stores database identically at all sites (correct)
Uses different database management systems at each site
Uses different data models at each site
Requires translations for query processing

What is a challenge of a heterogeneous distributed database?

Compatibility among different sites
Uniform schema and software usage
Easy query processing without translations
Lack of awareness among sites (correct)

How is data stored in the replication approach?

Stored redundantly at multiple sites (A) Signup and view all the answers

Why might a distributed database system be required?

To be accessed by various users globally (D) Signup and view all the answers

In a fully redundant database, what is the advantage of having copies of data maintained at different sites?

Increased availability of data at different sites and parallel processing of query requests (D) Signup and view all the answers

What is a disadvantage of maintaining copies of data at different sites in a fully redundant database?

Constant need for data updates and increased complexity of concurrency control (C) Signup and view all the answers

Which type of fragmentation ensures that each tuple is assigned to at least one fragment?

Horizontal fragmentation (D) Signup and view all the answers

What is the main advantage of a distributed database system over a centralized database system?

Higher availability, reliability, and better performance (A) Signup and view all the answers

What are the characteristics of a distributed database management system (DDBMS)?

Collection of logically related shared data, higher availability, and better performance (C) Signup and view all the answers

What makes a homogeneous database easy to manage?

All sites store database data identically (C) Signup and view all the answers

What is the primary challenge of a heterogeneous distributed database?

Different sites may use different schema and software (D) Signup and view all the answers

What is the purpose of translations in a heterogeneous distributed database?

To facilitate communication between different sites (B) Signup and view all the answers

In which type of distributed data storage approach is the entire relationship stored redundantly at 2 or more sites?

Replication (D) Signup and view all the answers

What defines a distributed database system as being located on various sites that don’t share physical components?

Heterogeneous database (A) Signup and view all the answers

In a distributed database system, what is the advantage of using fragmentation?

It distributes data and processing load to improve performance (D) Signup and view all the answers

What is a disadvantage of horizontal fragmentation in a distributed database system?

It complicates the process of reconstructing the original relation (D) Signup and view all the answers

What is the main challenge of maintaining a fully redundant database with copies of data at different sites?

Constant overhead due to data updating at all sites (B) Signup and view all the answers

What distinguishes a hybrid fragmentation from horizontal and vertical fragmentation?

It combines aspects of both horizontal and vertical fragmentation (A) Signup and view all the answers

Why does a distributed database system provide higher availability and reliability compared to a centralized database system?

It distributes data across multiple sites, allowing the system to continue functioning in case of site failure (A) Signup and view all the answers