How to execute stored procedure with input and output parameters using EF?

Question

I am using EF code first approach and I have created stored procedure using migration as following:

public override void Up()
    {
        Sql(@"CREATE TYPE IdsList AS TABLE   
                    ( 
                    Id Int
                    )
                    GO

                    Create Procedure getChildIds(
                    @IdsList dbo.IdsList ReadOnly
                    )
                    As
                    Begin
                    WITH RecursiveCTE AS
                    (
                        SELECT Id
                        FROM dbo.PhysicalObjects
                        WHERE ParentId in (Select * from @IdsList)
                        --Where Id=108
                        UNION ALL

                        SELECT t.Id
                        FROM dbo.PhysicalObjects t
                        INNER JOIN RecursiveCTE cte ON t.ParentId = cte.Id
                    )
                    SELECT * FROM RecursiveCTE
                    End");
    }

    public override void Down()
    {
        Sql(@"Drop Type IdsList
                Go
                Drop Procedure getChildIds");
    }

Now If I go to sql server management studio and execute the following scripts:

Declare @Ids dbo.IdsList

Insert into @Ids
SELECT 1

Exec getChildIds @Ids

It will execute successfuly, but Now I am trying to execute that stored procedure as following:

 var idsList = new SqlParameter {ParameterName = "idsList",  Value = new int[] { 1,2,3,4,5} };

 var idParams = new SqlParameter("idParams", SqlDbType.Structured)
            {
                Direction = System.Data.ParameterDirection.Output
            };

var results = dbContext.Database.SqlQuery<int>("getChildIds @idsList, @idParams out", idsList,idParams) ;

var idsResult = (List<int>)idParams.Value;

It does not return anything.

So how I could execute stored procedure with input and output parameters of type Table?

Answer 1

You will have to obtain your data a different way:

You cannot return data in a table-valued parameter. Table-valued parameters are input-only; the OUTPUT keyword is not supported.

Answer 2

I have solved it this way.

First of all I have updated my stored procedure to return Ids as following:

 public override void Up()
    {
        Sql(@"CREATE TYPE IdsList AS TABLE   
                    ( 
                    Id Int
                    )
                    GO

                    Create Procedure getChildIds(
                    @IdsList dbo.IdsList ReadOnly
                    )
                    As
                    Begin
                    WITH RecursiveCTE AS
                    (
                        SELECT Id
                        FROM dbo.PhysicalObjects
                        WHERE ParentId in (Select * from @IdsList)
                        UNION ALL

                        SELECT t.Id
                        FROM dbo.PhysicalObjects t
                        INNER JOIN RecursiveCTE cte ON t.ParentId = cte.Id
                    )
                    SELECT Id From RecursiveCTE
                    End");
    }

    public override void Down()
    {
        Sql(@" Drop Procedure getChildIds
               Go
               Drop Type IdsList
               ");
    }

And here how I have solved executing stored procedure using entity framework:

 var dataTable = new DataTable();
 dataTable.TableName = "idsList";
 dataTable.Columns.Add("Id", typeof(int));
 dataTable.Rows.Add(1);
 dataTable.Rows.Add(2);

  SqlParameter idsList = new SqlParameter("idsList", SqlDbType.Structured);
  idsList.TypeName = dataTable.TableName;
  idsList.Value = dataTable;

  var results = dbContext.Database.SqlQuery<int>("exec getChildIds @idsList", idsList).ToList();

I hope my code will help others having the same issue

Answer 3

The best solution for using user's procedures/functions and build-in functions in SQL is this library - https://github.com/Dixin/EntityFramework.Functions

It has great and easy implementation. Also it allows to follow code first approach

In your case you need to use Table-valued function

Define model

[ComplexType]
public class IdModel
{
     public int Id { get; set; }
}

Declare Type and Convention in DbContext

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    modelBuilder.Conventions.Add(new FunctionConvention<DbContext>());

    modelBuilder.ComplexType<IdModel>();

    base.OnModelCreating(modelBuilder);
}

Define function in DbContext

[Function(FunctionType.TableValuedFunction, nameof(ufnGetChildIds), Schema = "dbo")]
public IQueryable<IdModel> ufnGetChildIds([Parameter(DbType = "IdModel", Name = "IdsList")]List<IdModel> IdsList)
{
    ObjectParameter IdsListParameter = new ObjectParameter("IdsList", IdsList);

    return this.ObjectContext().CreateQuery<IdModel>(
        $"[{nameof(this.ufnGetChildIds)}](@{nameof(IdsList)})", IdsListParameter);
}

And use it from your DbContext

[TestMethod]
public void CallTableValuedFunction()
{
    using (DbContext database = new DbContext())
    {
        IQueryable<IdModel> employees = database.ufnGetChildIds(new List<IdModel> { new IdModel { Id = 1 }});
    }
}