Let's start our discussion by understanding the definitions of distributed versus decentralized databases.
A distributed database is a single logical database, which is installed on a set of computers that are geographically located at different locations and linked through a data communication network. Different types of distributed database are classified based on the number of different database management systems operating on each of the remote computers, how these remote DBMS communicate and work together, and if they need a controlling master resource to synchronize the data update requests to each of the database instances.
A decentralized database is a database that is installed on systems that are geographically located at different locations but "not" linked through a data communication network. This means that...