title: Error: column reference is ambiguous
body: <p>I have two tables from which i want to get the date without using joins.</p>
  
  <pre><code>id ProductVersion   productName  productDate
  1    p1.1            product1     2017-3-11
  2    p1.2            product1     2017-3-11
  3    p2.1            product2     2017-5-12
  4    p2.2            product2     2017-5-12
  5    p2.3            product2     2017-5-12
  6    p3.1            product3     2017-11-21
  7    p3.1            product3     2017-11-21
  </code></pre>
  
  <p>Table2</p>
  
  <pre><code>tid  productVersion  comments status       AvailableDate
  101    p1.1            Good     Sold          2017-3-11  
  102    p1.1            Good     Available     2017-3-12
  1009   p1.1            Good     Available     2017-3-12
  4008   p3.1            Average  NA            2017-11-11
  106    p3.2            Good     Sold          2017-5-14
  6      p3.1            Average  Available     2017-11-12
  </code></pre>
  
  <p>I have two tables as shown above.</p>
  
  <p>I want to get productVersion,productName,productDate,Comments,status column details from the above two tables.</p>
  
  <p>SQL Query(without joins):</p>
  
  <pre><code>select productversion t1,productName t1,productDate t1,comments t2,status t2 from table1 t1,table2 t2 
  where t1.productVersion = t2.productversion
  </code></pre>
  
  <p>Error message:</p>
  
  <pre><code>Error: column reference "productDate" is ambiguous.
  </code></pre>
  
  <p>Any inputs?</p>