Save changes in app MVC with Entity Framework

Hi.
I have a problem with my app, initially my app worked correctly and later send this error:
System.Data.Entity.Infrastructure.DbUpdateConcurrencyException' occurred in EntityFramework.dll but was not handled in user code
Additional information: Store update, insert, or delete statement affected an unexpected number of rows (0). Entities may have been modified or deleted since entities were loaded. Refresh ObjectStateManager entries.
please helpme.
it´s so important.
thanks.

Hi krloz.hdz,
-->System.Data.Entity.Infrastructure.DbUpdateConcurrencyException' occurred in EntityFramework.dll but was not handled in user code
this error offen occurs at the SaveChanges(). I suggest you change the state of the entity like below before savechanges().
db.overlayData.Attach(overlaydb1);
db.ObjectStateManager.ChangeObjectState(overlaydb1, EntityState.Modified);
db.SaveChanges();
If you still have questions, you could share your code with us, we could help you better.
Regards,
Youjun Tang
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It's cool. :)
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is a week that I document but I still have a bit of confusion.
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http://geekswithblogs.net/iupdateable/archive/2009/11/23/sql-azure-and-entity-framework-sessions-from-pdc-2009.aspx

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Sorry for the delay on this one. Let me know if you are still seeing this and I will see if we can get more diagnostic info somehow.
That error is basically an exception fault. It means a bug or a misconfiguration of Oracle Developer Tools. Can you try to reinstall ODT and see if you notice any unusual errors during install.. and see if a reinstall fixes the problem?

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