In Delphi, SetColumns is the protected method used to set the Columns property. In C++, SetColumns is the protected implementation of the Columns property. SetColumns calls the Assign method of the THTMLTableColumns object stored internally by TDSTableProducer. Thus, the memory for any columns object assigned to the Columns property is never owned or freed by TDSTableProducer. 

Columns 

Assign 

AssignTo