Missing schema in DBML if using LINQ to SP and Sp returning multiple record sets - linq

Question

while making of POC of LINQ to SQL and entities, i faced a problem stuck in a frozen dead end.
Problem is , am using LINQ to SP and every things was working fine and i made cool methods of editing, adding and deleting. Then some thing click in my mine that "what if i just return two record set from SP". i made a SP and returned two record set from it
SP look like this [Demo]
Create PROCEDURE [dbo].GetUserData
#UserId Bigint
AS
BEGIN
SET NOCOUNT ON;
-- Getting User
select * from [User] where id=#UserId
-- Getting User's role
select * from [Role] where userId=#UserId
end
then i droped that SP in my DBML (Linq to SQL classes) then here i noticed that only schema of one record set was created like this
<?xml version="1.0" encoding="utf-8"?>
<Database Name="MyInventory" Class="MyDBMLDataContext" xmlns="http://schemas.microsoft.com/linqtosql/dbml/2007">
<Connection Mode="AppSettings" ConnectionString="Data Source=MyDatabaseServer\;Initial Catalog=MyInventory;Integrated Security=True" SettingsObjectName="ConsoleApplication16.Properties.Settings" SettingsPropertyName="MyInventoryConnectionString" Provider="System.Data.SqlClient" />
<Function Name="dbo.GetUserData" Method="GetUserData">
<Parameter Name="UserId" Parameter="userId" Type="System.Int64" DbType="BigInt" />
<ElementType Name="GetUserDataResult">
<Column Name="Id" Type="System.Int64" DbType="BigInt NOT NULL" CanBeNull="false" />
<Column Name="Name" Type="System.String" DbType="VarChar(50) NOT NULL" CanBeNull="false" />
<Column Name="Email" Type="System.String" DbType="NVarChar(50)" CanBeNull="true" />
<Column Name="IsDeleted" Type="System.Boolean" DbType="Bit NOT NULL" CanBeNull="false" />
<Column Name="HomePage" Type="System.String" DbType="VarChar(100)" CanBeNull="true" />
</ElementType>
</Function>
</Database>
i can clearly see that only one record set is created of Users records and it is missing Role schema :(.
Can any body tell me what and why is that so?
Thanks
Lura

Answer 1

I have had to deal with something similar in getting multiple data sets from a data base for a website. What we did was create an DatabaseExtensions.cs file to add the queries with multiple data sets.
So in the extensions file we would have something like this
public partial class DataBaseDataContext
{
[ResultType(typeof(FirstResult))]
[ResultType(typeof(SecondResult))]
[Function(Name = "dbo.StoredProc")]
public IMultipleResults StoredProc([global::System.Data.Linq.Mapping.ParameterAttribute(DbType = "Int")] System.Nullable<System.Int> ID)
{
IExecuteResult result = this.ExecuteMethodCall(this, ((MethodInfo)(MethodInfo.GetCurrentMethod())), ID);
return ((IMultipleResults)(result.ReturnValue));
}
}
public class FirstResult;
public class SecondResult;
Note: I changed some of the names of things in this code to make it easier to read, so it may not work as is.
FirstResult and SecondResult are the result type classes. I would usually copy them from the dbml's accompanying .cs file then rename it. I didn't include their code here because it can be rather long.
DataBaseDataContext dataCon = new DataBaseDataContext();
var results = dataCon.StoredProc(id);
var firstSet = results.GetResult<FirstResult>();
var secondSet = results.GetResult<SecondResult>();
//process data
It is important to get your results out in the same order they come out in your stored procedure. After you have gotten your results out, you can use LINQ or whatever to work with them.

Answer 2

My finding is that if you add a result set to your dbml manually you get the results that you want but LinqToSql doesn't offer you a simple way to have access to them
Here is a path to your results
((System.Data.Linq.SqlClient.ObjectReaderCompiler.ObjectReaderSession
<System.Data.SqlClient.SqlDataReader>)
(((System.Data.Linq.SqlClient.SqlProvider.ExecuteResult)(result)).session)).buffer
you here have access to your result by index buffer[0] will return the results of your first select statement and buffer[1] returns the result of second select.
probably you can cast this two IEnumerables to typed IEnumerable<GetAllResult> and IEnumerable<GetAllResult1> although I didn't test that.
I build this sample dbml
<Function Name="dbo.GetAll" Method="GetAll">
<ElementType Name="GetAllResult">
<Column Name="ID" Type="System.Int32" DbType="Int" CanBeNull="true" />
<Column Name="Tagname" Type="System.String" DbType="NChar(10)" CanBeNull="true" />
</ElementType>
<ElementType Name="GetAllResult1">
<Column Name="Id" Type="System.Int32" DbType="Int" CanBeNull="true" />
<Column Name="TagId" Type="System.Int32" DbType="Int" CanBeNull="true" />
<Column Name="Name1" Type="System.String" DbType="NChar(10)" CanBeNull="true" />
</ElementType>
</Function>
and the generated cs file would be like this
[global::System.Data.Linq.Mapping.FunctionAttribute(Name="dbo.GetAll")]
[global::System.Data.Linq.Mapping.ResultTypeAttribute(typeof(GetAllResult))]
[global::System.Data.Linq.Mapping.ResultTypeAttribute(typeof(GetAllResult1))]
public IMultipleResults GetAll()
{
IExecuteResult result = this.ExecuteMethodCall(this, ((MethodInfo)(MethodInfo.GetCurrentMethod())));
return ((IMultipleResults)(result.ReturnValue));
}

Answer 3

Have you looked code generated for your model? Two resultsets will be here. Mapping can lie.
Ramesh