Given that cosmos db does not support group by, what is a good alternative to achieve similar functionality:
Select sum(*) , groupterm from tble group by gro
Group by is now supported in Cosmos db SQL API. You will be needing SDK version 3.3 or higher
Azure Cosmos DB currently supports GROUP BY in .NET SDK 3.3 or later. Support for other language SDK's and the Azure Portal is not currently available but is planned.
https://docs.microsoft.com/en-gb/azure/cosmos-db/sql-query-group-by