title: How does SQL join work?
body: <p>I am trying to understand how does joins work internally. What will be the difference between the way in which the following two queries would run?</p>
  
  <pre><code>For example
  
  (A)
  
  Select * 
  FROM TABLE1
  FULL JOIN TABLE2 ON TABLE1.ID = TABLE2.ID
  FULL JOIN TABLE3 ON TABLE1.ID = TABLE3.ID
  
  And
  
  (B)
  
  Select * 
  FROM TABLE1
  FULL JOIN TABLE2 ON TABLE1.ID = TABLE2.ID
  FULL JOIN TABLE3 ON TABLE2.ID = TABLE3.ID
  </code></pre>
  
  <p>Edit: I am talking about oracle here.
  Consider some records present in table 2 and table 3 but not in table 1, query A would give two rows for that record but B would give only one row.</p>