Attached is a sample SQL Adapter built on the ASDK. This adapter (being a sample), is rather simple:
(a) Only stored procedure execution is supported.
(b) For obtaining metadata about the result set returned by the stored procedure, the stored procedure is executed (GetSchemaOnly) with default values for each input parameter.
(c) Parameters are assumed to be either IN, or INOUT.
The adapter requires the Adventure Works sample database, which can be obtained from here: http://www.codeplex.com/MSFTDBProdSamples/Release/ProjectReleases.aspx?ReleaseId=4004. (I used AdventureWorksDB.msi).
There is a test project included which should help you out in figuring how the connection uri should look like. The test project browses, searches, and gets the metadata for a stored procedure. Then, it executes a procedure to get the ManagerId for a particular employee.