title: Checking 2 files in Unix and finding the sum of a particular column in 3rd file through shell script
body: <p>I have something I need help with, would appreciate your help 
  Let's take an example </p>
  
  <p>I have <strong>file 1</strong> with data </p>
  
  <pre><code>"eno", "ename", "salary"
  "1","john","50000"
  "2","steve","30000"
  "3","aku","20000"
  </code></pre>
  
  <p>and I have <strong>file 2</strong> with data </p>
  
  <pre><code>"eno", "ename", "incentives"
  "1","john","2000"
  "2","steve","5000"
  "4","akshi","200"
  </code></pre>
  
  <p>And the expected output in 3 file I want is :</p>
  
  <pre><code>"eno", "ename", "t_salary"
  "1","john","52000"
  "2","steve","35000"
  </code></pre>
  
  <p>This is what is expected result</p>
  
  <p>as I should be using eno and the ename as the primary key and output should be shown like this</p>