The software king of the world has lifted the kimono on a range of new features at Build, its annual developer conference mostly with a data theme.

This included the Cosmos DB, a replacement for, or upgrade to, Microsoft's Document DB NoSQL database. Vole touts Cosmos DB as being designed for "planet-scale" applications and giving developers fine control over the replication policies and reliability.

At the moment databases with strong consistency have to wait until data is fully replicated before a write is deemed to be complete. This comes at the expense of latency. Systems with eventual consistency mark operations as complete before data is fully replicated, promising only that the full replication will occur eventually. This improves latency but risks delivering stale data to applications.

Document DB used to offer four different options for the replication behaviour, but Cosmos DB increases that to five. It also scales the database span multiple regions, with Microsoft offering service level agreements (SLAs) for uptime, performance, latency, and consistency.

Vole will actually pay out if it misses the SLA requirements.

For those applications which demand traditional relational databases, Microsoft is adding both a MySQL and a PostgreSQL service. These will give the familiar open source databases in a platform-as-a-service style, removing the administrative overhead that comes of using them and making it easier to move workloads using them into Azure.

The company is offering a preview of a database-migration service that takes data from on-premises SQL Server and Oracle databases and migrates it to Azure SQL Database.

Azure SQL Database has a new feature in preview called "Managed Instances" that offers greater compatibility between on-premises SQL Server and the cloud variant, again to make workload migration easier, those attending Build were told.