title: Natural Join query in relational algebra?
body: <p>“Any relational algebra query that includes a natural join operator can also be expressed by an equivalent relational algebra query without a natural join operator”. Is it true or false</p>
  
  <p>I am on the fence with this question, I feel as though it is loaded.  I think it is true because:</p>
  
  <p>(Natural join) Output pairs of rows from the two input relations</p>
  
  <p>that have the same value on all attributes</p>
  
  <p>that have the same name.</p>
  
  <p>(Cartesian product) Output all pairs of rows from the two input</p>
  
  <p>relations (regardless of whether or not they</p>
  
  <p>have the same values on common attributes)</p>