Dealing With Optimistic Concurrency in Entity Framework

When you update a database record with the entity values, the database values are overwritten by the entity values (default behavior). In a real world situation it is quite possible that database values might have got changed after selecting them for modification. In such cases, your update operation might be overwriting changes made by someone else. That is why it becomes 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. To that end this article shows how to detect concurrency violation in EF and also the possible ways to deal with the situation.

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