title: how to compare 2 csv file base on multiple columns awk?
body: <p>I have 2 csv file with sample format as below ,, have ~ 5000 rows in each files : </p>
  
  <p>file 1: </p>
  
  <pre><code>    EMPLOYEE_NUMBER,LAST_NAME,FIRST_NAME,MIDDLE_NAME,BRANCH,DEPARTMENT,LEVEL,POSITION,EMAIL_ADDRESS
  110426,Balbon,Susan,Lagat,"abc Equity Ventures, Inc.",Group Internal Audit,Supervisor,I.S. Audit Supervisor,susan.balbon@abc.com
  30083,Mendezona,Bingen,Roemer,"abc Equity Ventures, Inc.",Risk Management Office,Vice President,VP - AEV Security,bing.mendezona@abc.test
  110773,Casas,Joyce Grace,Bea,"abc Equity Ventures, Inc.",Tax Advisory and Compliance,Manager,Tax Counsel,joyce.grace.casas@abc.com
  286,Fernandez,Mark Brian,Tato,abc Foundation Inc.,Computer Services Division,Supervisor,Senior Applications Supervisor,mark.fernandez@abc.com
  291,Plando,Marilou,Polleros,"abc Equity Ventures, Inc.",Administration,Assistant Vice President,AVP - Risk Management,marilou.plando@abc.test
  110813,Gemelo-Abarca,Therese Xyza,Dableo,"abc Equity Ventures, Inc.",Governance &amp; Compliance Team,Manager,Associate General Counsel - Corporate Secretarial and Compliance,therese.xyza.abarca@abc.com
  30096,Abay,Joanna Marie,Saluria,"abc Equity Ventures, Inc.",Tax Advisory and Compliance,Supervisor,Tax Compliance Officer,joanna.abay@abc.com
  110711,Ostan,Margilyn,Salibio,"abc Equity Ventures, Inc.",Accounting,Staff,Senior Accountant 1,margilyn.ostan@abc.com
  110732,Fumar-Gonzales,Vanessa Concepcion,Altarejos,"abc Equity Ventures, Inc.",Legal and Corporate Services,Manager,Associate General Counsel - Labor &amp; Litigation,vanessa.gonzales@abc.com
  </code></pre>
  
  <p>file 2 : </p>
  
  <pre><code>    EMPLOYEE_NUMBER,LAST_NAME,FIRST_NAME,MIDDLE_NAME,BRANCH,DEPARTMENT,LEVEL,POSITION,EMAIL_ADDRESS
  110426,Balbon,Susan,Lagat,"abc Equity Ventures, Inc.",Group Internal Audit,Supervisor,I.S. Audit Supervisor,susan.balbon@abc.com
  30083,Mendezona,Bingen,Roemer,"abc Equity Ventures, Inc.",Security,Vice President,VP - AEV Security,jetee.velante@abc.com
  110773,Casas,Joyce Grace,Bea,"abc Equity Ventures, Inc.",Tax Advisory and Compliance,Supervisor,Tax Counsel,joyce.grace.casas@abc.com
  286,Fernandez,Mark Brian,Tato,abc Foundation Inc.,Computer Services Division,Supervisor,Senior Applications Supervisor,mark.fernandez@abc.com
  291,Plando,Marilou,Polleros,"abc Equity Ventures, Inc.",Risk Management Office,Assistant Vice President,AVP - Risk Management,marilou.plando@abc.test
  110866,Dugan,Belinda,Escultura,"abc Equity Ventures, Inc.",Legal Management,Vice President,Vice President for Legal Services Management,dixie.dugan@abc.test
  221,Montehermoso,Gladys,Enoy,"abc Equity Ventures, Inc.",Accounting,Staff,Senior Accountant,gladys.montehermoso@abc.com
  30102,Oblianda,Anna Cielo,Salud,"abc Equity Ventures, Inc.",Accounting,Supervisor,Accounting Supervisor,cielo.oblianda@abc.com
  110499,Bucol,Charmaine Ann,Rebusa,"abc Equity Ventures, Inc.",Group Internal Audit,Staff,Audit Senior,charmaine.ann.bucol@abc.com
  </code></pre>
  
  <p>I would like to file all row have same  value in EMPLOYEE_NUMBER+EMAIL_ADDRESS columns but have different values in others columns using awk. </p>
  
  <p>My ideal is merge 2 csv file base on columns EMPLOYEE_NUMBER+EMAIL_ADDRESS  on vertical and remove duplicated row using awk. Thanks</p>
  
  <p>Output will like that : </p>
  
  <pre><code>EMPLOYEE_NUMBER,LAST_NAME,FIRST_NAME,MIDDLE_NAME,BRANCH,DEPARTMENT,LEVEL,POSITION,EMAIL_ADDRESS
  110773,Casas,Joyce Grace,Bea,"Aboitiz Equity Ventures, Inc.",Tax Advisory and Compliance,Manager,Tax Counsel,joyce.grace.casas@aboitiz.com
  110773,Casas,Joyce Grace,Bea,"Aboitiz Equity Ventures, Inc.",Tax Advisory and Compliance,Supervisor,Tax Counsel,joyce.grace.casas@aboitiz.com
  </code></pre>