OnDelete(DeleteBehavior.ClientCascade)没有删除实体条目，有什么问题？

public class Author
{
    public int Id { get; set; }
    public string Name { get; set; }

    public List<Book> Books { get; set; }
}

public class Book
{
    public int Id { get; set; }
    public string Title { get; set; }

    public int AuthorId { get; set; }
    public Author Author { get; set; }
}

public class Book
{
    public int Id { get; set; }
    public string Title { get; set; }

    public int AuthorId { get; set; }
    [ForeignKey("AuthorId")]
    [OnDelete(DeleteBehavior.ClientCascade)]
    public Author Author { get; set; }
}

dotnet ef migrations add InitialCreate
dotnet ef database update

SELECT 
    FK.name AS ForeignKey,
    PK.name AS PrimaryKey,
    FK.delete_referential_action_desc AS DeleteAction
FROM 
    sys.foreign_keys FK
INNER JOIN 
    sys.tables PK ON FK.referenced_object_id = PK.object_id
WHERE 
    PK.name = 'Books';