private void detach_Categories2(Categories entity)
 {
     this.SendPropertyChanging();
     entity.Categories1 = null;
 }
 private void attach_Categories2(Categories entity)
 {
     this.SendPropertyChanging();
     entity.Categories1 = this;
 }
 partial void UpdateCategories(Categories instance);
 partial void DeleteCategories(Categories instance);
 partial void InsertCategories(Categories instance);