title: Is CROSS JOIN a synonym for INNER JOIN without ON clause?
body: <p>I am wondering whether <code>CROSS JOIN</code> can be safely replaced with <code>INNER JOIN</code> in any query when it is found.</p>
  
  <p>Is an <code>INNER JOIN</code> without <code>ON</code> or <code>USING</code> exactly the same as <code>CROSS JOIN</code>? If yes, has the <code>CROSS JOIN</code> type been invented only to express intent better in a query?</p>
  
  <p>An appendix to this question would be:</p>
  
  <p>Can there be a difference using modern and widely used DBMSes when using <code>CROSS JOIN ... WHERE x</code>,  <code>INNER JOIN ... ON ( x )</code> or <code>INNER JOIN ... WHERE ( x )</code> ?</p>
  
  <p>Thank you.</p>