16:50:34 ERROR: SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '1220' for key 'views'

The sql is: UPDATE eps_product SET views = views + 1 wHeRe id = '184'

in D:\xampp\chanzhi\system\lib\base\dao\dao.class.php on line 1306, request: http://www.xhdz.org/en/product/184.html, last called by D:\xampp\chanzhi\system\lib\base\dao\dao.class.php on line 760 through function sqlError.
in D:\xampp\chanzhi\system\framework\base\router.class.php on line 2120 when visiting product-view-184