How to Retrieve a Database-Assigned Entity ID After Insertion with Entity Framework?

Getting Your Entity ID After an Entity Framework Insert

When you insert a new entity into your database using Entity Framework, you'll often need the database-assigned ID for subsequent operations. This article explains how to efficiently retrieve this ID.

Although Entity Framework provides an ID property, this initially holds a temporary identifier, not the actual database ID. To get the database-generated ID, a slightly different method is required.

The Solution

Entity Framework elegantly handles ID retrieval for automatically generated keys (like IDENTITY in SQL Server). Simply add your entity to the relevant ObjectSet and call SaveChanges on the ObjectContext. The ID property of your entity will then be updated with the database-assigned value.

<code class="language-csharp">using (var context = new MyContext())
{
  context.MyEntities.Add(myNewObject);
  context.SaveChanges();

  int id = myNewObject.Id; // id now contains the database-generated ID
}</code>

Internally, Entity Framework uses SCOPE_IDENTITY() (or a similar function depending on your database) to fetch the newly inserted entity's ID when auto-generated keys are in use. This ensures you get the correct ID without extra coding.

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