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Author: msdeep14

src/BPtree.cpp

@@ -339,7 +339,7 @@ int BPtree::insert_record(int primary_key, int record_num){
  Btreenode n(true);
  int q, j, prop_n, prop_k, prop_new, curr_node = root_num;
  bool finish = false;
- std::stack < int >S;
+ std::stack < int > S;
  //read all the data of node stored in file tree%d.data (%d==curr_node=root_num=file_no);
 //now n contains all the previously stored data;
  read_node(curr_node, n);
@@ -396,9 +396,9 @@ int BPtree::insert_record(int primary_key, int record_num){
  //copy remaining values to other node created(new_node);
  new_node.copy_last(temp, j);
  //return keys[j-1];
- prop_k = temp.get_key(j);
+ prop_k = temp.get_key(j); // key to be moved to new root
  prop_new = files_till_now;
- prop_n = curr_node;
+ prop_n = curr_node; // node that is splitted at first place
  //write back the two new nodes created to their respective files;
  write_node(files_till_now, new_node);
  write_node(curr_node, n);
@@ -413,7 +413,10 @@ int BPtree::insert_record(int primary_key, int record_num){
  /*Last element splitted was root
  so create new root and assign meta_data */
  Btreenode nn(false);
+ // insert key to new root
  nn.push_key(prop_k);
+ // insert two pointer associated to this key
+ // for left and right
  nn.push_pointer(prop_n);
  nn.push_pointer(prop_new);
  files_till_now++;