404 error page for database driven pages

Sorry for my bad english but i hope you would understand my query.

How can i set 404 not found for database driven pages..?


I am using header("HTTP/1.0 404 Not Found"); in my 404 error page and ErrorDocument 404 /404.html, whereas 404.html is my error page.

i have an URL http://www.example.com/folder/my-test-for-url-95/ which is opening correctly because it has existence on database. but when i am opening http://www.example.com/folder/my-test-for-url-951/ which has existence on database is also opening without any information but i want here a 404 not found page. How can i do so.


Thanks

 

if(mysql_num_rows($result)==0){

header("Location: 404.html");​

}