title: Power Query creating dupes upon Left Join
body: <p>I am trying to merge two tables to get 3 columns from the other table and it is creating 4 additional duplicate rows (in the actual report, which has led to more than 2 million rows). I have created a sample here and it even did the same thing to that. I was wondering if somebody could help me out here. I am doing a left outer join and have made sure that the tables do not have duplicates beforehand. </p>
  
  <p>I am attaching screenshots of my sample file here:</p>
  
  <p><a href="https://i.stack.imgur.com/I8IvD.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/I8IvD.png" alt="enter image description here"></a> (Attendance)</p>
  
  <p><a href="https://i.stack.imgur.com/adVyn.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/adVyn.png" alt="enter image description here"></a> (Classes)</p>
  
  <p><a href="https://i.stack.imgur.com/I3xk9.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/I3xk9.png" alt="enter image description here"></a> (Merge Query with dupes)</p>