cosmetic changes

Author: msdeep14

build/BPtree.o

@@ -1,5 +1,8 @@
 /*
-// code references : DFC query builder by BUG_ASSASINS team
+ // code references : DFC query builder by BUG_ASSASINS team
+ // File : BPtree.cpp
+ // Author : extra modifications and optimizations done by Mandeep Singh
+ // Purpose : store indexed data to disk
 */
 
 #include "BPtree.h"
@@ -220,7 +223,7 @@ void BPtree :: write_node(int filenum, Btreenode n){
  sprintf(str, "table/%s/tree/tree%d.dat", tablename,filenum);
  std::ofstream out_file(str, std::ofstream::binary | std::ofstream::out | std::ofstream::trunc);
  free(str);
- //write data to out_file root=n()
+ //write data to out_file root = n()
  out_file << n;
  out_file.close();
 }
@@ -266,7 +269,7 @@ BPtree :: BPtree(char table_name[]){
  out_file.write((char *) (&root_num), sizeof(root_num));
  out_file.close();
 
- //initialize with root node =leaf node;
+ //initialize with root node = leaf node;
  Btreenode root(true);
  //set next_node=-1; as it is root;
  root.set_next(-1);
@@ -304,11 +307,10 @@ Btreenode BPtree::search_leaf(int primary_key){
  //Traversing the Tree from root till leaf
  while (!n.isleaf()){
  q = n.num_pointers();
- //check primary key if it is smaller than the key[0]
  if (primary_key <= n.get_key(1)){
  //set curr_node =pointers[0];
  curr_node = n.get_pointer(1);
- }//check if primary key is greater than key[q-1];// q==size of vector keys;
+ }
  else if (primary_key > n.get_key(q - 1)){
  //set curr_node = pointers[q-1];
  curr_node = n.get_pointer(q);
@@ -329,7 +331,7 @@ int BPtree::get_record(int primary_key){
  int pos = n.get_next_key(primary_key) + 1;
  clock_t stop=clock();
  double elapsed=(double)(stop-start)*1000.0/CLOCKS_PER_SEC;
- printf("\nTime elapsed for search is %f ms",elapsed);
+ printf("\nTime elapsed for search is %f ms\n",elapsed);
  if (pos <= n.num_keys() && n.get_key(pos) == primary_key){
  return n.get_pointer(pos);
  }else{
@@ -339,22 +341,22 @@ int BPtree::get_record(int primary_key){
 
 /* A function the inserts a (key, record_num) pair in the
  B+ Tree */
-//key is first coloumn of database either can be int or varchar;
+// key is first coloumn of database either can be int or varchar;
 int BPtree::insert_record(int primary_key, int record_num){
-//printf("pri %d\n record_num %d",primary_key,record_num);
-  //Btreenode n= leaf=true, next_node =-1;
+ //printf("pri %d\n record_num %d",primary_key,record_num);
+ // Btreenode n= leaf=true, next_node =-1;
  Btreenode n(true);
  int q, j, prop_n, prop_k, prop_new, curr_node = root_num;
  bool finish = false;
  std::stack < std::pair<int, Btreenode> > 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 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);
 
- //Traverse the tree till we get the leaf node;
+ // Traverse the tree till we get the leaf node;
  while (!n.isleaf()){
- S.push(make_pair(curr_node,n)); //Storing address in case of split
- //num_pointers==function that returns size of pointers vector from the block file;
+ S.push(make_pair(curr_node,n)); // Storing address in case of split
+ // num_pointers==function that returns size of pointers vector from the block file;
  q = n.num_pointers();
  if (primary_key <= n.get_key(1)){
  curr_node = n.get_pointer(1);
@@ -363,24 +365,23 @@ int BPtree::insert_record(int primary_key, int record_num){
  }else{
  curr_node = n.get_pointer(n.get_next_key(primary_key) + 1);
  }
- //get all the data of node n from file tree%d.dat(%d==curr_node);
+ // get all the data of node n from file tree%d.dat(%d==curr_node);
  read_node(curr_node, n);
  }
 
- //Here n is Leaf Node
- //if key exist exist then return;
- //key exist
+ // Here n is Leaf Node
+ // if key already exists then return ERROR
  if (n.search_key(primary_key)) {
  return BPTREE_INSERT_ERROR_EXIST;
  }
 
+ /*
+ if n is not full, insert key and pointer to node
+ write back node to file, update meta_data and return
+ */
  if (!n.full()){
- //leaf node empty insert here and exit
  n.insert_key(primary_key, record_num);
- //n is updated now;
-//now write this node back to file;
  write_node(curr_node, n);
- //update meta-data after key is inserted successfully;
  update_meta_data();
  return BPTREE_INSERT_SUCCESS;
  }
@@ -389,27 +390,32 @@ int BPtree::insert_record(int primary_key, int record_num){
  Btreenode temp(true), new_node(true);
 
  temp = n;
- //insert the key and pointer into n i.e. temp now;
  temp.insert_key(primary_key, record_num);
  j = ceil((BPTREE_MAX_KEYS_PER_NODE + 1.0) / 2.0);
- //if max_key_per_node = 30;; j=16;
- //copy the first half values to new node(temp) created;
+ // if max_key_per_node = 4, j = 3
+ // copy the first j values of temp to node n
+ // and remaining to new_node
  n.copy_first(temp, j);
  //now one file is increased to store the new node;
  files_till_now++;
- // set new_node to returned next_node;
+ // next pointer of new_node will be next pointer of n
+ // and next pointer of n will be newly created node new_node
  new_node.set_next(n.get_next());
  n.set_next(files_till_now);
- //copy remaining values to other node created(new_node);
  new_node.copy_last(temp, j);
- //return keys[j-1];
+
+ /*
+ prop_k is key to be inserted into root
+ and prop_new and prop_n are pointers to
+ be attached to this root value
+ */
  prop_k = temp.get_key(j); // key to be moved to new root
  prop_new = files_till_now;
- prop_n = curr_node; // node that is splitted at first place
- //write back the two new nodes created to their respective files;
+ prop_n = curr_node;
+
+ // write back the two new nodes created
  write_node(files_till_now, new_node);
  write_node(curr_node, n);
- //empty keys[] and pointers[];
  temp.clear_data();
  new_node.clear_data();
 

build/bin/deepdb

@@ -28,45 +28,46 @@
 #include "file_handler.h"
 
 int record_size(table *temp){
-int size=0;
-temp->prefix[0]=0;
-for(int i=0;i<temp->count;i++){
+int size = 0;
+temp->prefix[0] = 0;
+for(int i = 0; i < temp->count; i++){
 switch(temp->col[i].type){
 case INT:
-temp->prefix[i+1]=sizeof(int)+temp->prefix[i];
-size+=sizeof(int);
+temp->prefix[i+1] = sizeof(int) + temp->prefix[i];
+size += sizeof(int);
 break;
 case VARCHAR:
-temp->prefix[i+1]=sizeof(char)*(MAX_VARCHAR +1) +temp->prefix[i];
-size+=sizeof(char)*(MAX_VARCHAR +1);
+temp->prefix[i+1] = sizeof(char)*(MAX_VARCHAR +1) + temp->prefix[i];
+size += sizeof(char)*(MAX_VARCHAR + 1);
 break;
 }
 }
 return size;
 }
 
-table * create_table(char name[],int count){
+table * create_table(char name[], int count){
 //set to check for duplicate enteries of columns;
 std::unordered_set <string> create_col_set;
 table *toreturn = new table();
-table *temp=new table();
-temp->fp=NULL;
-temp->blockbuf=NULL;
-strcpy(temp->name,name);
-temp->name[strlen(name)]='\0';
-temp->count=count;
-temp->rec_count=0;
-temp->data_size=0;
+table *temp = new table();
+temp->fp = NULL;
+temp->blockbuf = NULL;
+strcpy(temp->name, name);
+temp->name[strlen(name)] = '\0';
+temp->count = count;
+temp->rec_count = 0;
+temp->data_size = 0;
 
 //enter the data for columns of table
-int i=0;
-cout<<"Enter column name,Data type(1.int 2.varchar) and max size(max allowed int=6,char=99) of column\n";
-for(i=0;i<count;i++){
-string type;
-string size;
-string temp_col_name;
-cin>>temp_col_name>>type>>size;
-//check if the column name is already entered, if not make a entry in set and allow input
+int i = 0;
+cout << "\nEnter column name,Data type(1.int 2.varchar) and max size(max allowed int=6,char=99) of column\n";
+for(i = 0; i < count; i++){
+std::string type;
+std::string size;
+std::string temp_col_name;
+std::cin >> temp_col_name >> type >> size;
+
+// check if the column name is already entered, if not make a entry in set and allow input
 if(create_col_set.count(temp_col_name) == 0){
 strcpy(temp->col[i].col_name,temp_col_name.c_str());
 create_col_set.insert(temp_col_name);
@@ -75,8 +76,8 @@ table * create_table(char name[],int count){
 return NULL;
 }
 
-//check if entered datatype no. is correct
-if(type.length()>1){
+// check if entered datatype no. is correct
+if(type.length() > 1){
 printf("\nwrong input(datatype should be (1=int or 2=varchar))\nexiting...\n\n");
 printf("-------------------------------------------------------------------------\n");
 return NULL;
@@ -89,7 +90,7 @@ table * create_table(char name[],int count){
 return NULL;
 }
 }
-//check size input;
+// check size input;
 if(size.length() > 2){
 printf("\n123wrong input\nmax size(max allowed int=6,char=99), exiting...\n");
 printf("---------------------------------------------------------------------\n");
@@ -124,7 +125,7 @@ table * create_table(char name[],int count){
 }
 }
 }
-if(i<count){
+if(i < count){
 printf("\n\tYou have not entered all details of columns\n\n");
 return NULL;
 }
@@ -137,19 +138,20 @@ table * create_table(char name[],int count){
 void create(){
 char *name;
 int count;
-name=(char*)malloc(sizeof(char)*MAX_NAME);
-cout<<"Enter table name: ";
-cin>>name;
+name = (char*)malloc(sizeof(char)*MAX_NAME);
+std::cout << "\nEnter table name: \n";
+std::cin >> name;
 
 //check if new table already exists in table list or not
 int check = search_table(name);
 if(check == 1){
-cout << "\nERROR!\n" << name << " already exists\n";
-cout << "\n------------------------------------------------\n";
+std::cout << "\nERROR!\n" << name << " already exists\n";
+std::cout << "\n------------------------------------------------\n";
 return;
 }
-FILE *fp=fopen("./table/table_list","r+");
-if(fp==NULL) cout<<"file pointer is null\n";
+FILE *fp = fopen("./table/table_list","r+");
+if(fp == NULL)
+std::cout<<"file pointer is null\n";
 
 // char tab_name[20];
 // while(fscanf(fp,"%s",tab_name)!=EOF){
@@ -159,9 +161,9 @@ void create(){
 //	}
 // }
 
-//enter table details if not exist
-cout<<"enter no. of columns: ";
-cin>>count;
+// enter table details if not exist
+std::cout << "\nenter no. of columns: \n";
+std::cin >> count;
 table *temp;
 temp=create_table(name,count);
 if(temp != NULL){
@@ -170,14 +172,14 @@ void create(){
 if(temp!=NULL){
 temp->blockbuf = malloc(temp->BLOCKSIZE);
 FILE *fpr;
-  fpr = open_file(temp->name, const_cast<char*>("w"));
-  fwrite(temp->blockbuf, 1, temp->BLOCKSIZE, fp);
-  fclose(fpr);
-  store_meta_data(temp);
-  free(temp->blockbuf);
+ fpr = open_file(temp->name, const_cast<char*>("w"));
+ fwrite(temp->blockbuf, 1, temp->BLOCKSIZE, fp);
+ fclose(fpr);
+ store_meta_data(temp);
+ free(temp->blockbuf);
 free(temp);
 
-//if its a new table, make a entry inside table_list
+// if its a new table, make a entry inside table_list
 fseek(fp,0,SEEK_END);
 fprintf(fp,"%s\n",name);
 fclose(fp);
@@ -190,5 +192,4 @@ void create(){
  //printf("\nwrong input\nexiting...\n\n");
  return;
  }
-
 }