Oracle Oracle9i database server 9.0.1.x allows local users to access restricted data via a SQL query using ANSI outer join syntax.
http://www.securityfocus.com/bid/4523
http://www.iss.net/security_center/static/8855.php
http://www.ciac.org/ciac/bulletins/m-071.shtml
http://otn.oracle.com/deploy/security/pdf/sql_joins_alert.pdf