EF Core by Patrik

Disconnected Scenario

Make EF Core update only the updated properties by turning the disconnected scenario to connected.

public void SaveBook(Book book)
{
    // Here, 'book' is the book with the changed Title.
    using(var context = new TestContext())
    {
        var dbBook = context.Books.Find(book.ID);

        // Copy book's property values to dbBook.
        context.Entry(dbBook).CurrentValues.SetValues(book);

        context.SaveChanges();
    }
}

There may be good reasons to prefer the latter method above the former.