Description
EF Core 3.0.1
I insert an object along with related objects. Then I set the state of the object to "Detached". I then perform another call to .SaveChangesAsync().
Observed behavior: the related objects are deleted.
Expected behavior: the related objects should not be deleted; rather their tracking status should simply be set to "Detached".
(This is a breaking change since upgrading from EF Core 2.2.4)
Steps to reproduce
public class Thing
{
[Key]
public Guid ThingId { get; set; }
[MaxLength(200)]
public string Description { get; set; }
public List<OwnedByThing> OwnedByThings { get; set; } = new List<OwnedByThing>();
}
public class OwnedByThing
{
[Key]
public Guid OwnedByThingId { get; set; }
public Guid ThingId { get; set; }
public Thing Thing { get; set; }
public int Value { get; set; }
}
await using var db = new MyDbContext();
var thing = new Thing
{
Description = "Hello world thing",
OwnedByThings = new List<OwnedByThing>
{
new OwnedByThing {Value = 1},
new OwnedByThing {Value = 2}
}
};
db.Things.Add(thing);
await db.SaveChangesAsync();
var thingCount = await db.Things.CountAsync(e => e.ThingId == thing.ThingId);
Assert.AreEqual(1, thingCount, "Thing Count A");
var ownedCount = await db.OwnedByThings.CountAsync(e => e.ThingId == thing.ThingId);
Assert.AreEqual(2, ownedCount, "Owned count A");
db.Entry(thing).State = EntityState.Detached;
await db.SaveChangesAsync();
thingCount = await db.Things.CountAsync(e => e.ThingId == thing.ThingId);
Assert.AreEqual(1, thingCount, "Thing Count B");
ownedCount = await db.OwnedByThings.CountAsync(e => e.ThingId == thing.ThingId);
Assert.AreEqual(2, ownedCount, "Owned count B");
Result:
Owned count B
Expected: 2
But was: 0
Further technical details
EF Core version: 3.0.1
Database provider: Npgsql
Target framework:.NET Core 3.0
Operating system: Windows 10 Pro
IDE: JetBrains Rider