Re: object algebra

> And now please write a query that returns an aggregate age of all persons.
> In this schema with SQL, or with Neo's school science fair project.

// Psuedo code to calc age of all unique persons under selected node // Step thru unique descendant's of God

   int ageTotal = 0;
   int* pDesc_a[kMAX_TREE_DEPTH] = {pGod};    while (int i = T_Relatives(pDesc_a, kCREATURE, kUNIQUE)){

     int* pThing = pDesc_a[i];
     if (IsAncestorOf(pPersonCls, pThing)){
       int* pAge = T_Property_get(pThing, pAgeCls);
       if (pAge){
         sAge = T_Symbol_get(pAge);
         ageTotal = ageTotal + ConvertSymbolToInteger(sAge);
       }
     }

XDb1 has transitive closure.
For actual code to a related problem, see www.xdb1.com/Example/Ex075b.asp Received on Thu Feb 26 2004 - 02:09:33 CET