EF 4.1 代码优先：执行存储过程并返回 IDENT

Question

I'm attempting to use context.Database to execute a stored proc that inserts a record and returns the identity. I know my proc works, using either an output parameter, select, or return, but I cannot get either ExecuteSqlCommand or SqlQuery<int> to return the identity.

Using a stored proc with return,

INSERT INTO TableA (FieldA, FieldB)
RETURN SCOPE_IDENTITY

I see a return value of 1010966 from SSMS

DECLARE @return_value int
EXEC    @return_value = spInsertRecord
SELECT  'Return Value' = @return_value

But nothing I have done in my application returns a valid value.

Int64 result = context.Database.ExecuteSqlCommand

always returns 3 and I get a casting error referencing Decimal when using SqlQuery<int> . I made an attempt with an output parameter, but wasn't able to get the code to execute properly, so have focused on the app consuming either SELECT SCOPE_IDENTITY or RETURN SCOPE_IDENTITY

Short of creating models to replace the logic contained in the stored procedure, I'm open to any and all suggestions for returning the value for both the Stored Proc and application level.

Answer 1

Here is how you can get this to work. In this example, my EntityManager is just a class that inherits from DBContext.

Test Table:

CREATE TABLE [dbo].[TableA](
    [ID] [int] IDENTITY(1,1) NOT NULL,
    [FieldA] [nvarchar](50) NULL,
    [FieldB] [nvarchar](50) NULL
) ON [PRIMARY]

Stored Proc:

CREATE PROC spInsertRecord
    @FieldA NVARCHAR(50),
    @FieldB NVARCHAR(50)
AS

INSERT  TableA
    (FieldA, FieldB)
VALUES  
    (@FieldA, @FieldB)

SELECT  CAST(@@IDENTITY AS INT)

Calling Code (VB.NET)

Public Shared Function AddRecord(FieldA As String, FieldB As String) As Integer
    Try
        Using EM As New EntityManager
            Return EM.Database.SqlQuery(Of Integer)(
                "EXEC spInsertRecord @FieldA, @FieldB",
                New SqlParameter("FieldA", FieldA),
                New SqlParameter("FieldB", FieldB)).SingleOrDefault
        End Using
    Catch ex As Exception
        Throw New ApplicationException("An error occurred while executing AddRecord", ex)
    End Try
End Function

Consuming Code:

Return AddRecord("Tom", "Halladay")

My result is the incrementing return value. Hope this helps.