WCF Data Services

WCF Data Services replaces the ADO.Net Data Services; WCF Data Services helps us to expose data in a standardized format from datasource using Open Data Protocol (OData) which can be consumed by any application/service by placing a REST format HTTP Request.

WCF Data Services are available as part of Visual Studio 2010. WCF Data Services can be created on Data Models which are created using the ADO.Net Entity Data Model; they also support data models that are based on common language runtime (CLR) objects that return an instance of the IQueryable interface. This helps us to create data services for data which is placed in lists, arrays, and collections in the .NET Framework. To enable create, update, and delete operations for these data structures, we must implement the IUpdatable interface.

ADO.Net Data Services

ADO.Net Data Services implement the OData protocol to expose data to all applications in a standardized way. The OData Protocol aims in standardizing the way in which data is shared between applications so that any application/service can access data from other applications/services without having to know the underlying storage mechanism.

OData exposed data to applications in REST format HTTP URIs, to perform CRUD (create/read/update/delete) operations on the data source. The response to the request is sent in XML Based ATOM format or text based JSON format.

What is OData?

OData is an acronym of Open Data Protocol, as the name suggests OData is a protocol to standardize the way data is shared between various applications. The OData Protocol aims in standardizing data access between applications in such a way that any application can read data from any provider without the knowledge of the underlying storage format.

OData provides a standard data model to represent the data and a standard protocol which can be used by client applications to request data from the provider. To standardize the process of data sharing, OData uses some of the standard web technologies HTTP, ATOM and JSON for data sharing.