What does a distributed database consist of?

A distributed database consists of data that is stored across different machines, which are interconnected through a network. This architecture allows for data to be distributed in various locations, enabling more efficient data management, improved performance, and increased reliability. By having data spread across multiple servers, a distributed database can enhance availability and fault tolerance; if one machine fails, others can continue to operate and provide access to the data.

Additionally, this setup offers the potential for load balancing, as the distribution of data can optimize the use of resources and minimize single points of failure. The data in a distributed system can be synchronized to ensure consistency and can support larger databases that may exceed the capacity of a single machine.

The other options describe configurations that do not align with the definition of a distributed database. For example, data residing solely on a single machine or in a single centralized database contradicts the principle of distribution, which is central to the concept in question. Similarly, limiting storage only to the cloud does not encompass the full scope of what a distributed database can be, since it may also include on-premises machines and various types of network connections aside from cloud storage.