Set Oracle to force searching string by upper case

Question

Our application using Oracle 11.1 and Hibernate. Data store in our database in mix cases. many of our queries are like select first_name from persons where upper(first_name) like 'DAV%'
It returns Dave, DAVE, dave, David, DAVIE etcAccording to our developers, Hibernate does not send query select first_name from persons where upper(first_name) like 'DAV%' it only doesselect first_name from persons where first_name like 'DAV%'This only return DAVE and DAVID.
Question: Is there a way to set Oracle, at database level or table level, to always search by upper case, that is, select first_name from persons where first_name like 'DAV%' is converted to select first_name from persons where upper(first_name) like 'DAV%'

Answer 1

Yes, there is a way. New in 10GR2....
You can set NLS_COMP.
http://www.orafaq.com/node/91
I tested it and it works well...
Example: SQL>  alter session set NLS_COMP=ANSI;
Session altered.
SQL> alter session set NLS_SORT=BINARY_CI;
Session altered.
SQL> select name from names where name = 'Johny Jacobson';
NAME
Johny Jacobson
johny jacobson
JOHNY JACOBSONI hope you find this helpful.
ji li