Casting collection from one db table to add to another db table - asp.net-mvc

Question

Below is a chunk of my ActionMethod. The part I'm struggling with is casting a new variable integers with all IntegerBufferValues from db.IntegerBuffers and then adding them to db.IntegerList.
var integers = new ICollection<Integers>();
const int COUNT = 1000000;
Stopwatch watch = Stopwatch.StartNew();
for (int c = 0; c < COUNT; c++)
{
integers = db.IntegerBuffers.OrderBy(i => i.IntegerBufferValue);
};
watch.Stop();
var integerList = new IntegerList
{
Direction = direction,
Performance = watch.ElapsedMilliseconds,
Integers = integers
};
db.IntegerLists.Add(integerList);
IntegerList
namespace Project.Models
{
public class IntegerList
{
public int IntegerListID { get; set; }
public string Direction { get; set; }
public long Performance { get; set; }
public virtual ICollection<Integer> Integers { get; set; }
}
}
IntegerBuffer
namespace Project.Models
{
public class IntegerBuffer
{
public int IntegerBufferID { get; set; }
public int IntegerBufferValue { get; set; }
}
}
Edit: To show Integer class.
Integer
namespace IntegerSorterApp.Models
{
public class Integer
{
public int IntegerID { get; set; }
public int IntegerValue { get; set; }
public int IntegerListID { get; set; }
public virtual IntegerList IntegerList { get; set; }
}
}

Answer 1

integers is currently a collection of IntegerBuffer objects. Use .Select to project them to just integers:
IEnumerable<int> integers;
// ...
integers = db.IntegerBuffers
.OrderBy(i => i.IntegerBufferValue)
.Select(i => i.IntegerBufferValue);
Or:
integers =
from buffer in db.IntegerBuffers
orderby buffer.IntegerBufferValue
select buffer.IntegerBufferValue;
Then, you assign to the collection, you could do something like this:
var integerList = new IntegerList
{
Direction = direction,
Performance = watch.ElapsedMilliseconds,
Integers = integers.ToList()
};
Update:
Oops, I didn't see that Integer is a class. My answer is to create a list of Int32 objects. The basics still apply: you'll need to use select to project to whatever structure you need. Now I don't understand your data model, but perhaps you want something like this:
// Create your list first so that the list ID is saved
var integerList = new IntegerList
{
Direction = direction,
Performance = watch.ElapsedMilliseconds,
};
db.IntegerLists.Add(integerList);
// Now create your Integer records with the ID of the list
foreach (var buffer in db.IntegerBuffers.OrderBy(b => b.IntegerBufferValue))
{
db.Integers.Add(new Integer
{
IntegerValue = buffer.IntegerBufferValue,
IntegerListID = integerList.IntegerListID
});
}
If this is a one-to-many relationship, which it appears to be, then setting IntegerListID on your Integer record will implicitly add it to the Integers collection of the list.