Entity Framework - Virtual Property is inserting data in respective table - entity-framework

Question

Not sure about title of the question, anyways! I have my Model Class RandomStuff which has Environment as Virtual Property.
public class RandomStuff
{
//NOT SHOWN ON FORM HIDDEN JUST TO MAKE IT EASIER IN DB
[Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
[Newtonsoft.Json.JsonProperty]
public int JobId { get; set; }
[Required]
[ForeignKey("Environment")]
[Newtonsoft.Json.JsonProperty]
[DataMember(IsRequired = true)]
public int EnvironmentId { get; set; }
[Newtonsoft.Json.JsonProperty ]
public virtual Environment Environment { get; set; }
}
My Environment is as below:-
[Newtonsoft.Json.JsonObject(Newtonsoft.Json.MemberSerialization.OptIn)]
[DataContract]
public class Environment
{
[Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
[Newtonsoft.Json.JsonProperty]
public int Id { get; set; }
[Required]
[Newtonsoft.Json.JsonProperty]
[DataMember(IsRequired = true)]
public string Name { get; set; }
}
Now, in my controller I have :-
public HttpResponseMessage Save(RandomStuff stuff)
{
if (ModelState.IsValid)
{
//Some stuff here
db.RandomStuffs.Add(stuff);//When this excutes, it is
//inserting data in Environment table also.
db.SaveChanges();
}
}
Now, whenever i am adding stuff to my RandomStuff table, it is adding Environment also.
EDIT:
I'll try to explain with general example, which I took from ef-inserting-duplicate-parent-objects
public class Foo
{
public int FooId {get;set;}
public virtual ICollection<Bar> Bars {get;set;}
}
public class Bar
{
public int BarId {get;set;}
public strung BarName {get;set;}
}
Now, if above being my model structure. I am trying to add one Foo data to my DB.
db.Foo.Add(new Foo{
FooId=1,
Bars=new List<Bar>(){
new Bar{
BarId=2,
BarName="Something"
}
}
})//Something of this sort will be my data, which needs to be inserted
//Now this record "new Bar{BarId=2, BarName="Something"}" is already present in DB
Now, what is happening is, it is inserting data in Foo table with id=1 and it is also adding duplicate in Bars table with id 2.
Also if I use something like below, my requirement is fulfilled:
db.Entry(fooModelDataComingFromSomewhere.Bars).State = EntityState.Unchanged;

Answer 1

Your question still isn't quite clear, as you are now providing code snippets from another post that aren't even in the same structure as the code you are having an issue with. However, I'm still guessing that your issue is with duplicate inserts, so I'll try to provide a suggestion.
When you use the Add() Method on the Entity Framework DB Context, it marks the entire graph of connected objects as Added, even if the item already exists in the database. A common situation that you are probably seeing is that when you Add an object of type RandomStuff it is also adding a new object of type Environment, and though Environment.Name is the same, Environment.Id is Database assigned, and since Entity Framework has marked the entire graph as Added, it creates a new Environment object, with the same Name but a new Id. therefore, you have multiple Environment rows in your table with the same Name.
The solution is deceptively simple. Since you already have a Property on your RandomStuff object to hold the Foreign Key representing the Environment object, instead of adding a new Environment object to the graph, simply create your RandomStuff object and add the value of the EnvironmentId. In other words,
Instead of creating a new RandomStuff Object this way:
var RandomStuff randomStuff = new RandomStuff {
Environment = new Environment {
Name = "Existing Environment"
}
}
create it like this:
var RandomStuff randomStuff = new RandomStuff {
EnvironmentId = existingEnvironment.Id
}