execute stored procedure from SqlQuery data reader issue

Question

so i am trying to execute my stored procedure as folowing

            String sql =
        "SET NOCOUNT ON; " +
        "DECLARE @id INT, @itemnumber nvarchar(20); " +
        "SELECT @id= '" + car.ID + "'" +
        "EXEC [file].[usp_iudCar] " +
        "@p_ID=@id OUTPUT," +
        "@p_Location= '" + location + "', " +
        "@p_ItemNumber=@itemnumber OUTPUT, " +
        "@p_DoerTicket= '" + userToken + "' " +
        "SELECT @id AS id, @itemnumber AS itemNumber; ";

            QueryParamCollection queryParams = new QueryParamCollection();
            queryParams.AddInt32Param(QueryParamName.CarID, (object)car.ID);
            queryParams.AddStringParam(QueryParamName.Location, (object)location);
            queryParams.AddStringParam(QueryParamName.DoerTicket, (object)userToken);

            var update = context.Database.SqlQuery<Int32>(sql).FirstOrDefault<Int32>();

            return update;

similar to when i doing it from query on the server as

   DECLARE @return_value int,
            @p_ID int,
            @p_ItemNumber nvarchar(20)

    SELECT  @p_ID = 1783999

    EXEC    @return_value = [file].[usp_iudCar]
            @p_ID = @p_ID OUTPUT,
            @p_ItemNumber = @p_ItemNumber OUTPUT,
            @p_Location = N'test',
            @p_DoerTicket = N'0x0100000057065fc3a91f34c3f1f9cad41e2f5889bac6a68d3eab408dddc1cd54e57ce240565294f481f4f248bca4fb772d38fd737a6448dcbbfd9d58'

    SELECT  @p_ID as N'@p_ID',
            @p_ItemNumber as N'@p_ItemNumber'

    SELECT  'Return Value' = @return_value

    GO

result set

but i gets an execption

"ExceptionMessage": "The data reader has more than one field. Multiple fields are not valid for EDM primitive or enumeration types.",

so how do i fix that or what is the correct way to do this?

Answer 1

This error:

"ExceptionMessage": "The data reader has more than one field. Multiple fields are not valid for EDM primitive or enumeration types.",

means that your stored procedure returns more than just one field. This is what you are telling EF:

var update = context.Database.SqlQuery<Int32>(sql).FirstOrDefault<Int32>();

that the query returns a single field but clearly that is not the case or you would not get that error.

Also that is not how to call a stored procedure using EF database first approach. Please refer this question and accepted answer for how to do what you want the proper way.