ChangeConflictException: Row not found or changed.

While I was working and for the first time I got this error. It was really frustrating because all that I was just doing was simply updating a record using LINQ.

Example:

public void UpdateContact(Guid id, string firstName, string lastName, string middleName) {

	var updateQry = _db.Contacts.Single(con => con.ID == id);
	updateQry.firstName = firstName;
	updateQry.lastName = lastName;
	updateQry.middleName = middleName;

	_db.SubmitChanges();
}

After some research I have found out that I only have to do was to recreate the table that was on the DBML designer simply by deleting the table(on my case it was the Contacts table) and redragging it back again.

But maybe there are some cases that this might not work too. There are some cases that there is another method that is also updating or altering the row but on my case I am really sure that there is no other code or method that is updating that row. So you might want to check it out that kind of scenario.

There are also some cases that you have changed some Column properties like you have changed a NOT NULL Column to NULL Column. This is also to ge considered as LINQ needs to be synchronized with your Database. So any changes to Database must be immediately be get reflected to your DBML file.