Hi, Could you please help me in this issue. I have a foreign key on a child table referencing the primary key of the parent table. I have created the index on the foreign key on the child table. Now, how do I know that the foreign key constraint is using the index or not. I tried to see the index name from user_constarints table, but it always shows empty. When index_name is empty, what does it mean, even though I have it. Thanks nagu __________________________________________________________________ Switch to Netscape Internet Service. As low as $9.95 a month -- Sign up today at http://isp.netscape.com/register Netscape. Just the Net You Need. New! Netscape Toolbar for Internet Explorer Search from anywhere on the Web and block those annoying pop-ups. Download now at http://channels.netscape.com/ns/search/install.jsp -- //www.freelists.org/webpage/oracle-l