Copy tree and set new database id's

I'm trying to copy a tree. The tree is saved in an SQLite database and I load this into a treeview. The table structure is like: id,parent,level,position. In the treeview the id is given to the node object. Now I want to copy the tree recursively. It is necessary to generate new id's and set the parent id's correct:

procedure copyTree(machineId, parent : integer; startNode : TTreeNode);
var
  tmpId : integer;
  tmpData : TAssignmentData; // Record
begin
  if assigned(startNode) then
  begin
    //Read out data from existing node
    tmpData := data.getAssignment(integer(startnode.Data));
    //Set node data to new machine
    tmpData.machine := machineId;
    //If node is on the top level
    if tmpData.parent <> 0 then
      tmpData.parent := parent;
    //Write dataset (new node) to the database
    tmpId := data.insertAssignment(tmpData);

    copyTree(machineId, tmpId, startnode.getFirstChild);
    copyTree(machin开发者_StackOverflow中文版eId, tmpId, startnode.getNextSibling);
  end;
end;

I've tried this code, but the parent id's are not set correct in the database. The assignment is lost. Where is my mistake?

Best regards ...

Assuming data.insertAssignment(tmpData); returns the new id for a node then only that node's children should have their parent id set to tmpId. You are setting the next sibling's parentid to tmpId as well!

copyTree(machineId, tmpId, startnode.getNextSibling);

Consider just passing parent for sibling nodes:

copyTree(machineId, parent, startnode.getNextSibling);