D365 includes its own data warehouse (actually data mart) designed for financial reporting however as per now it can’t be extended to support other business areas. The solution favorited by Microsoft for DW seems to be the use of an Azure SQL Database aka BYOD (Bring Your Own Database) to which entity-based data can be exported incrementally (aka incremental push) or fully (aka full push) via the Data Management Framework (DMF) packages.
Because many of the D365 tables (e.g. Inventory Transactions, Products, Customers, Vendors) were overnormalized over the years and other tables were added as part of new functionality, to hide this complexity, Microsoft introduced a new layer of abstraction formed from data entities organized within an entity store. Data entities are view-like encapsulations of the underlying D365 table schema, the data import/export from and D365 being performed extensively over these data entities via the DMF, which extends the Data Import/Export Framework (DIXF).
One can use thus a BYOD as a direct source for other reporting tools as long they support a connection to Azure, otherwise the data can be further loaded into a database into the cloud, which seems to be the best option until now, as long the organization has other data that need to be consolidated for reporting. From here on, one deals with the traditional way of reporting and the available infrastructure can be extended to use an additional data source.
The BYOD solution comes with several restrictions: a package needs to be created for each business unit, no composite data entities can be exported, data entities that don’t have a unique key can’t be exported via an incremental push, data entities can change over times (new versions being available), while during synchronization no active locks should be on the database. In addition, organizations which followed this path report also some bugs that needed to be addressed via the Microsoft support. Even if the about 1700 available data entities facilitate to some degree data consumption, they seem to be more appropriate for data migrations and data integrations than for DW workloads.
In absence of direct SQL connectivity, in theory organizations can still use SSIS or similar integration tools to connect to D365 production databases and consume data entities via the Open Data Protocol (OData), a standard that defines a set of best practices for building and consuming RESTful APIs. Besides some architectural challenges, loading big tables with transactional data is reportedly slow and impracticable for loading a data warehouse. Therefore, the usability of such an architecture becomes limited in time.
Microsoft imposed a hard limitation upon its D365 architecture by making its production database inaccessible. Of course, there’s still time for Microsoft to do some magic and pull new solutions from the technology stack hat. Unfortunately, the constraints imposed to the production environments limit organizations’ choices of building a modern and flexible data warehouse. For the future it would be great if the DMF could be used directly with standard SQL Server databases, avoiding thus the need for the intermediary Azure database, or if a real-time operational solution could be provided out-of-the-box. We’ll see what the future brings...