Context SqlQuery<>() without detailing all columns - entity-framework

Question

Let's say I have a Person entity with 3 columns:
public PERSON {
public int OID { get; set; }
public string NAME { get; set; }
public string SURNAME { get; set; }
}
I want to query it with raw SQL but without specifying all columns so I write:
var query = "select NAME, SURNAME from PERSON";
var list = context.SqlQuery<PERSON>(query).ToList();
But it throws Exception:
System.Data.Entity.Core.EntityCommandExecutionException : The data reader is incompatible with the specified '...'. A member of the type, 'OID', does not have a corresponding column in the data reader with the same name.
So it seems like it tries to map all columns, and, if some are missing, it throws.
Is there a way to make it ignore columns that are not present in raw SQL query and map just the columns that are accessible?
The reason is, I have a lot of columns for some entities and sometimes I just want to query partial columns. I don't want to create new class with just the necessary columns for each query.

Answer 1

I can think of 3 options off the top of my head that could work for you.
Option 1: Rewrite your queries and use a standard Linq query:
var persons = from p in context.Persons
select new PERSON
{
NAME = p.NAME,
SURNAME = p.SURNAME
};
Option 2: Return a dummy value for columns you don't need
var query = "select 0 AS OID, NAME, SURNAME from PERSON";
var list = context.SqlQuery<AlmostPERSON>(query).ToList();
Option 3: Create your own intermediate classes with the columns you need from the database:
public class AlmostPERSON
{
public string NAME { get; set; }
public string SURNAME { get; set; }
}
var query = "select NAME, SURNAME from PERSON";
var list = context.SqlQuery<AlmostPERSON>(query).ToList();
You could even project this intermediate class onto your standard entity like this:
var list = context.SqlQuery<AlmostPERSON>(query)
.Select(ap => new PERSON
{
NAME = ap.NAME,
SURNAME = ap.SURNAME
})
.ToList();

Answer 2

Found one more possible solution: using ADO.NET IDataReader with AutoMapper
public List<T> ExecuteFor<T>(string sql)
{
using (_connection = new OracleConnection(_connectionString))
{
_connection.Open();
using (var command = new OracleCommand(sql, _connection))
{
using (OracleDataReader reader = command.ExecuteReader())
{
Mapper.CreateMap<IDataReader, List<T>>();
return Mapper.Map<IDataReader, List<T>>(reader);
}
}
}
}