Create a Program to Implement Inner Join in C++ Assignment Solution.

#include

#include

#include

#include

#include

using namespace std;

vector> read_csv(string file_name)

{

/*

This function will read the content of file_name into a vector of vectors

Each sub vector represents a row of data.

For each file, the first line is always skipped because it is assumed that it contains the header

*/

vector> data;

vector row;

string line;

ifstream myFile(file_name);

if(!myFile.is_open()) {

cout << "Could not open file " << file_name << endl;

exit(1);

}

if(myFile.good())

{

// read first line which is the header

getline(myFile, line);

string val;

while(getline(myFile, line)) {

stringstream ss(line);

row.clear();

while(getline(ss, val, ',')) {

row.push_back(val);

}

data.push_back(row);

}

myFile.close();

}

return data;

}

vector> inner_join(vector> table1, vector> table2) {

/*

Given two vectors of vector, this function will apply an inner-join to the two

datasets, based on the id of the customer. Then, this function will return a vector of vector containing that

data in the format of ID,NAME,AGE,MAKE,MODEL,YEAR

*/

// Create the vector to store output

vector> output;

// Now, for each user in table1, check if there is one car in table2

int id1, id2, age, year;

string name, make, model;

vector row;

for(int i =0; i < table1.size(); i++) {

id1 = stoi(table1[i][0]);

name = table1[i][1];

age = stoi(table1[i][2]);

// Loop through elements from table 2

for(int j = 0; j < table2.size(); j++)

{

id2 = stoi(table2[j][0]);

make = table2[j][1];

model = table2[j][2];

year = stoi(table2[j][3]);

if(id1 == id2)

{

// Append to output

row.clear();

row.push_back(to_string(id1));

row.push_back(name);

row.push_back(to_string(age));

row.push_back(make);

row.push_back(model);

row.push_back(to_string(year));

output.push_back(row);

}

}

}

return output;

}

void write_csv(string file_name, vector> data)

{

/*

This function receives a vector of vector and appends each row of data

into a csv file

*/

ofstream myFile(file_name);

myFile << "ID,NAME,AGE,MAKE,MODEL,YEAR" << endl;

for(int i = 0; i < data.size(); i++)

{

myFile << data[i][0] << "," << data[i][1] << "," << data[i][2] << "," << data[i][3] << "," << data[i][4] << "," << data[i][5] << endl;

}

myFile.close();

}

int main() {

// Read Table1.csv

vector> table1 = read_csv("Table1.csv");

// Read Table2.csv

vector> table2 = read_csv("Table2.csv");

// Apply Inner-Join

vector> result = inner_join(table1, table2);

// Now, write output

write_csv("Output.csv", result);

}