OData over SQL Azure Federations project contains samples of OData services that expose data from a federated SQL Azure database.
These samples brings together WCF Data Service reflection data provider and Entity Framework to build an OData service that exposes a data from a federated database.
First sample uses EF database first model.
Second sample uses EF POCO model. This service does not support $expand option.
Fan-out queries are not fully supported. Only one "root" collection can be queried directly. Queries to other collections should contain a federation key value.
You can download the source code and read the documentation about how to make it work.
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