EF Concurrency Processing Timestamp attribute in Model First approach

I am trying to implement the solution given in Concurrency Handling using the Entity Framework in an ASP.NET MVC application .

The article says:

Adding a tracking property to a department object

In the \ Department.cs models, add the tracking property:

[Timestamp] 
public Byte[] Timestamp { get; set; }

The Timestamp attribute indicates that this column will be included in the Where clause of the Update and Delete commands sent to the database.

Since I am using the first approach of the model , I followed steps 1-5 outlined in Creating a Timestamp Column with Entity Framework

• Add a property named "Timestamp" for the object in the EF model.
• Set type to binary
• Set nullable to false
• StoreGeneratedPattern
• ConcurrencyMode .

, \Department.cs

    public virtual byte[] Timestamp
    {
        get;
        set;
    }

Timestamp:

// Metadata for Department entity
public class DepartmentMetadata
{
    [Timestamp]
    public byte Timestamp { get; set; }
}

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