Top Five Things to Know About Modeling Web Services
Applies to: SharePoint Server 2010
You should know the following five things about modeling Web and WCF services in the Microsoft Business Connectivity Services (BCS):
Your modeling depends on the behaviors of the methods that are provided by the Web/WCF service, and how they are programmed.
To determine what methods are provided by a Web/WCF service, look at the proxy generated by SVCUTIL.EXE.
Make your choices for Finder, SpecificFinder, Association, and other methods by comparing the in and out parameters of the different Web/WCF methods.
For each external content type, you should identify the fields that uniquely identify an instance of that type. Without an identifier, Business Data Connectivity (BDC) service cannot uniquely identify an Entity instance. The data returned by a back-end application method is just a blob of data without identifiers. Only if the returned data also has identifiers can the data have semantic meaning in the BDC, and only then can you implement actions, search on, and crawl the external content.
Name child TypeDescriptor entities by using the name of the Microsoft .NET Framework accessor in the .NET Framework type referenced by the parent TypeDescriptor. You can find these .NET Framework types in the Microsoft Visual C# proxy generated by SVCUTIL.EXE. The child TypeDescriptors of TypeDescriptors that have the IsCollection flag set, however, can be named anything you choose.