Joining a database table with a Dictionary
I am trying to join a db table with a List of objects which have two values [int ID, double Value] where int - is ID in the table, and double is some percentage.
I want to get the result from the database with LINQ so that the result will be sorted by the double Value in the object.
Here i开发者_如何学Pythons a sample code:
var sortedDict = (from entry in SimilarDealPercentage orderby entry.Value descending select entry).ToDictionary(pair => pair.Key, pair => pair.Value);
List<SimilarityRatio> temptable = new List<SimilarityRatio>();
foreach (KeyValuePair<int, double> pair in sortedDict)
{
SimilarDealIds.Add(pair.Key);
SimilarityRatio sr = new SimilarityRatio();
sr.ID = pair.Key;
sr.Value = pair.Value;
temptable.Add(sr);
}
var qfinal = from d in DB.Deals
from s in temptable
where (d.Id == s.ID)
orderby s.Value descending
select d;
This gives the following error:
Unable to create a constant value of type 'NineOwl.DAL.Managers.SimilarityRatio'. Only primitive types ('such as Int32, String, and Guid') are supported in this context.
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