Two Ways of Handling Concurrency Violations in Entity Framework Code First

When you update an entity and call SaveChanges() to save the values back in the database, the existing values for that record are overwritten by the new entity values. This is the default behavior in entity framework code first. In a real world situation it is quite possible that database values might have got changed after you select them for modification. In such cases, your update operation might be overwriting changes made by someone else. This is concurrency violation. And it is important to detect if concurrency violation has occurred. You can then take some corrective action or at least inform the user about such a violation.

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