Which type of database is needed?

While cloud databases can offer high availability, they are not inherently distributed. A cloud database can be a single instance that may not provide the same level of redundancy as a distributed system. If the cloud provider experiences an outage affecting a specific region, access to data could be compromised unless a distributed architecture is implemented.

Relational databases focus on structured data and relationships but do not inherently provide high availability features. While they can be configured for redundancy, a standard relational database setup does not guarantee the distributed nature necessary for maintaining data access during outages, making it less suitable in this scenario.

Flat-file databases consist of a single file structure without any complex relationships or redundancy. They lack the capability to distribute data across multiple locations, which makes them highly vulnerable to outages. Consequently, a flat-file database would not meet the requirements for high availability in the event of local or regional failures.