Customers can use elastic scaling to increase throughput and store capacity based on global demand. The system should deliver the requested throughput within 5 seconds at 99th percentile from the time that the request was made.
Customers can build mission-critical, highly responsive applications. The system must guarantee predictable and guaranteed 99th percentile end-to-end read and write latency.
Make sure that the system is always available. The system must be available at 99.99 percent regardless of the number or regions of their database. Customers will be able to test the end to end availability properties of applications (in steady state). The service must also allow customers the ability to simulate regional failures and mark regions associated to their database offline. This allows applications to validate their end-to-end availability.
Allow developers to create correct, globally distributed applications. The system must provide a predictable and intuitive programming model that is based on data consistency. Strong consistency is not free. However, large, distributed applications written against a “eventually consistent”, database result in application code that is difficult to understand, brittle, and riddled with errors.
Provide comprehensive, financially-backed comprehensive SLAs [service level agreements] for 1, 2, 3, and 4 above.
Reduce the burden on developers for database schema/index management, versioning, and other tasks. Globally distributed applications find it difficult to keep the database schema and its indexes in sync.
Natively support multiple data formats and popular APIs to access data. It is necessary to efficiently translate between externally exposed APIs, and internal data representation.
To pass the savings on to customers, operate at a very low price.
Guthrie stated that Azure Cosmos DB meets these design goals. “Azure Cosmos DB allows for elastic scaling across any number of geographic regions while delivering industry’s only financially-backed data SLA across availability. latency. throughput and consistency.” Azure Cosmos DB is the only schema-agnostic database. It indexes data automatically so you can run blazing fast queries and not have to deal with complicated schema and index management.