As you know Microsoft has retrieve the data from Hadoop with by polybase and extended the R language to External language(R and Phython). now Microsoft is wanted to make sure that it has feasibility for all the environment whichever is available in the market. earlier I blog on MongoDB which is happening and favorable to developers for document store and containers concept, CosmosDB is the similar architecture of MongoDB for horizontal data storage , container and Document with the help of DocumentDB.
Microsoft has introduced many things recently(SQL 2016/17):
SQL Server on Linux
SQL Server – PolyBase (Hadoop Compatibility- data retrieval)
Azure SQL Server – CosmosDB – MongoDB
This indicates that Microsoft do not want to be isolated on Windows platform nor want to restrict to small scale… and Its been proved that Microsoft is doing great on this area… the only thing I believe is the SME for those new concepts which has been introduced unless we do not know how to manage it we may not be expert of doing it so.