void MT::CollectStats () { GiSTpath path; path.MakeRoot (); GiSTnode *node = ReadNode (path); if (!node->IsLeaf()) { int maxLevel = node->Level(); double *radii = new double[maxLevel]; int *pages = new int[maxLevel]; for (int i=0; i<maxLevel; i++) { pages[i] = 0; radii[i] = 0; } TruePredicate truePredicate; GiSTlist<GiSTentry*> list = node->Search(truePredicate); // retrieve all the entries in this node double overlap = ((MTnode *)node)->Overlap(); double totalOverlap = overlap; delete node; while (!list.IsEmpty()) { GiSTentry *entry = list.RemoveFront (); path.MakeChild (entry->Ptr()); node = ReadNode (path); overlap = ((MTnode *)node)->Overlap(); totalOverlap += overlap; pages[node->Level()]++; radii[node->Level()] += ((MTkey *) entry->Key())->MaxRadius(); GiSTlist<GiSTentry*> newlist; if (!node->IsLeaf()) { newlist = node->Search(truePredicate); // recurse to next level } while (!newlist.IsEmpty()) { list.Append (newlist.RemoveFront ()); } path.MakeParent (); delete entry; delete node; } // output the results cout << "Level:\tPages:\tAverage_Radius:"<<endl; int totalPages = 1; // for the root for (int i=maxLevel-1; i>=0; i--) { totalPages += pages[i]; cout << i << ":\t" << pages[i] << "\t" << radii[i]/pages[i] << endl; } cout << "TotalPages:\t" << totalPages << endl; cout << "LeafPages:\t" << pages[0] << endl; cout << "TotalOverlap:\t" << (float)totalOverlap << endl; delete []radii; delete []pages; } else { delete node; } }
GiSTentry* GiSTnode::SearchPtr(GiSTpage ptr) const { for (int i=0; i<numEntries; i++) { GiSTentry *e = (*this)[i]; if (e->Ptr() == ptr) return (GiSTentry*) e->Copy(); } return NULL; }
GiSTentry* GiSTcursor::Next() { GiSTpage page; while (first || !stack.IsEmpty()) { if (first) { page = GiSTRootPage; first = 0; } else { assert(lastlevel >= 0); GiSTentry *entry = stack.RemoveFront(); if (entry->IsLeaf()) return entry; // Pop off the stack for (int i=0; i < entry->Level() - lastlevel; i++) path.MakeParent(); page = entry->Ptr(); delete entry; } // Entry was a pointer to another node path.MakeChild(page); GiSTnode *node = gist.ReadNode(path); lastlevel = node->Level(); GiSTlist<GiSTentry*> list = node->Search(*query); while (!list.IsEmpty()) { GiSTentry *entry = list.RemoveRear(); stack.Prepend(entry); } delete node; } // The search is over... return NULL; }
void GiST::DumpNode (ostream& os, GiSTpath path) const { GiSTnode *node = ReadNode(path); node->Print(os); if (!node->IsLeaf()) { TruePredicate truePredicate; GiSTlist<GiSTentry*> list = node->Search(truePredicate); while (!list.IsEmpty()) { GiSTentry *e = list.RemoveFront(); path.MakeChild(e->Ptr()); DumpNode (os, path); path.MakeParent(); delete e; } } delete node; }
// SearchMinPenalty returns where a new entry should be inserted. GiSTpage GiSTnode::SearchMinPenalty(const GiSTentry &newEntry) const { GiSTentry *minEntry = NULL; GiSTpenalty *minPenalty = NULL; for (int i=0; i<numEntries; i++) { GiSTentry *e = (*this)[i]; assert(e->Node() == this); GiSTpenalty *penalty = e->Penalty(newEntry); if (minEntry == NULL || (*penalty) < (*minPenalty)) { minEntry = e; if (minPenalty) delete minPenalty; minPenalty = penalty; } else delete penalty; } delete minPenalty; return minEntry->Ptr(); }
void CommandSelect(const char *table, const GiSTpredicate& pred) { int i; i = GetTable(table); if (i == NOT_FOUND) { cerr << "Table is not open!\n"; return; } GiST *gist = tables[i].gist; GiSTcursor *c = gist->Search(pred); GiSTentry *e; while ((e = c->Next()) != NULL) { Record* rec = (Record*)e->Ptr(); cout << rec->value << "\n"; delete e; } delete c; }
void GiST::Split(GiSTnode **node, const GiSTentry& entry) { int went_left=0, new_root=0; if((*node)->Path().IsRoot()) { new_root=1; (*node)->Path().MakeChild(store->Allocate()); } GiSTnode *node2=(*node)->PickSplit(); node2->Path().MakeSibling(store->Allocate()); GiSTentry *e=(*node)->SearchPtr(entry.Ptr()); if(e!=NULL) { went_left=1; delete e; } node2->SetSibling((*node)->Sibling()); (*node)->SetSibling(node2->Path().Page()); WriteNode(*node); WriteNode(node2); GiSTentry *e1=(*node)->Union(); GiSTentry *e2=node2->Union(); e1->SetPtr((*node)->Path().Page()); e2->SetPtr(node2->Path().Page()); // Create new root if root is being split if (new_root) { GiSTnode *root=NewNode(this); root->SetLevel((*node)->Level()+1); root->InsertBefore(*e1, 0); root->InsertBefore(*e2, 1); root->Path().MakeRoot(); WriteNode(root); delete root; } else { // Insert entry for N' in parent GiSTpath parent_path=(*node)->Path(); parent_path.MakeParent(); GiSTnode *parent=ReadNode(parent_path); // Find the entry for N in parent GiSTentry *e=parent->SearchPtr((*node)->Path().Page()); assert(e!=NULL); // Insert the new entry right after it int pos=e->Position(); parent->DeleteEntry(pos); parent->InsertBefore(*e1, pos); parent->InsertBefore(*e2, pos+1); delete e; if(!parent->IsOverFull(*store)) WriteNode(parent); else { Split(&parent, went_left? *e1: *e2); GiSTpage page=(*node)->Path().Page(); (*node)->Path()=parent->Path(); (*node)->Path().MakeChild(page); page=node2->Path().Page(); node2->Path()=(*node)->Path(); node2->Path().MakeSibling(page); } delete parent; } if(!went_left) { delete *node; *node=node2; } else delete node2; delete e1; delete e2; }
void MXTree::Split(GiSTnode **node, const GiSTentry& entry) { double radii[2], dist, *dists = new double[(*node)->NumEntries()*2]; int pageNums[2], cands[2]; vector<vector<int>> vec(2); ((MXTnode *)(*node))->TestPromotion(radii, &dist, pageNums, cands, dists, vec); if (Trade((*node)->Path().IsRoot(), radii, dist, pageNums, ((MXTnode *)(*node))->GetPageNum()+1, (*node)->NumEntries())) { // don't split now delete[] dists; GiSTpath oldPath = (*node)->Path(); int startPage = ((*node)->Path().IsRoot() ? rootPage : (*node)->Path().Page()); int pageNum = ((MXTnode *)(*node))->GetPageNum(); ((MXTfile *)store)->Deallocate(startPage, pageNum); startPage = ((MXTfile *)store)->Allocate(++pageNum); (*node)->Path().MakeSibling(startPage); rootPage = ((*node)->Path().IsRoot() ? startPage : rootPage); ((MXTnode *)(*node))->SetPageNum(pageNum); WriteNode(*node); if (!(*node)->Path().IsRoot() && startPage != oldPath.Page()) { GiSTpath parentPath = oldPath; parentPath.MakeParent(); GiSTnode *parentNode = ReadNode(parentPath); GiSTentry *e = parentNode->SearchPtr(oldPath.Page()); assert(e != NULL); int pos = e->Position(); e->SetPtr(startPage); parentNode->DeleteEntry(pos); parentNode->InsertBefore(*e, pos); WriteNode(parentNode); delete parentNode; delete e; } } else { // split now bool bLeft = false, bNewRoot = false; if ((*node)->Path().IsRoot()) { bNewRoot = true; (*node)->Path().MakeChild(rootPage); rootPage = store->Allocate(); } int oldPageNum = ((MXTnode *)(*node))->GetPageNum(); GiSTnode *node2 = ((MXTnode *)(*node))->PickSplit(cands, dists, vec); delete[] dists; int curPageNum = ((MXTnode *)(*node))->GetPageNum(); assert(oldPageNum >= curPageNum); if (oldPageNum > curPageNum) { ((MXTfile *)store)->Deallocate((*node)->Path().Page()+curPageNum, oldPageNum-curPageNum); } node2->Path().MakeSibling(((MXTfile *)store)->Allocate(((MXTnode *)node2)->GetPageNum())); WriteNode(*node); WriteNode(node2); GiSTentry *e = (*node)->SearchPtr(entry.Ptr()); if (e != NULL) { bLeft = true; delete e; } GiSTentry *e1 = (*node)->Union(); GiSTentry *e2 = node2->Union(); e1->SetPtr((*node)->Path().Page()); e2->SetPtr(node2->Path().Page()); // Create new root if root is being split if (bNewRoot) { GiSTnode *root = NewNode(this); root->SetLevel((*node)->Level() + 1); root->InsertBefore(*e1, 0); root->InsertBefore(*e2, 1); root->Path().MakeRoot(); WriteNode(root); delete root; } else { // Insert entry for N' in parent GiSTpath parentPath = (*node)->Path(); parentPath.MakeParent(); GiSTnode *parent = ReadNode(parentPath); // Find the entry for N in parent GiSTentry *e = parent->SearchPtr((*node)->Path().Page()); assert(e != NULL); // Insert the new entry right after it int pos = e->Position(); parent->DeleteEntry(pos); parent->InsertBefore(*e1, pos); parent->InsertBefore(*e2, pos+1); delete e; if (!parent->IsOverFull(*store)) { WriteNode(parent); } else { Split(&parent, bLeft? *e1: *e2); // parent is the node which contains the entry inserted GiSTpage page = (*node)->Path().Page(); (*node)->Path() = parent->Path(); // parent's path may change (*node)->Path().MakeChild(page); page = node2->Path().Page(); node2->Path() = (*node)->Path(); node2->Path().MakeSibling(page); } delete parent; } if (!bLeft) { delete *node; *node = node2; // return it } else { delete node2; } delete e1; delete e2; } }
int PtrPredicate::Consistent (const GiSTentry& entry) const { return !entry.IsLeaf() || entry.Ptr()==page; }