inline __fastcall virtual
      TDBISAMBaseDataSet(System::Classes::TComponent* AOwner) :
      Data::Db::TDataSet(AOwner) { } 

Use the New operator to create an instance of a TDBISAMBaseDataSet component using the constructor. However, you should not use this constructor to create an instance of this component directly. Instead you should create an instance of a TDBISAMTable or TDBISAMQuery component, which both descend from this component and provide a published interface for use at design-time.