Do not call Destroy directly in an application. Instead, call Free, which verifies that the TRDSConnection reference is not nil before calling Destroy 

Destroy closes all active datasets and closes its connection before freeing all internal resources. 

Destroyperforms the following tasks: 

Clears references. 

Frees its data space object. 

Calls the inherited destructor. 

Create 

System::TObject::Free