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Is query to new added object possible in MS Entity Framework

Is there a way to query or just access newly added object (using ObjectContext.AddObject method) in Entity Framework? I mean situation when it is not yet saved to data store using SaveChanges

I understand that queries are translated to underlying SQL and executed against data store, and it don't have this new object yet. But anyway, I'm curious - if it is not oficially supported, maybe it is possible in theory. If it's not, how developer can deal with it? Manually track new objects and query them using Linq to objects?

The same question also applies to LinqToSql.

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Vladekk Avatar asked Nov 28 '08 16:11

Vladekk


2 Answers

In EF, if you use this code, you have all the entities that are already loaded in the context (including newly added ones) :

context.ObjectStateManager.GetObjectStateEntries(EntityState.Added | EntityState.Modified | EntityState.Unchanged).Select(o => o.Entity).OfType<YourObjectType>()
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Johann Blais Avatar answered Nov 15 '22 03:11

Johann Blais


"The same question also applies to LinqToSql."

For LINQ-to-SQL, look at DataContext.GetChangeSet(); this has 3 separate collections for the pending .Inserts, .Updates and .Deletes

Note that the ChangeSet is a snapshot of when the GetChangeSet() method is called; you need to re-query to see any additional changes.

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Marc Gravell Avatar answered Nov 15 '22 05:11

Marc Gravell