Look at the following example:
SQL>create table alphanum (codes varchar(10)); SQL>insert into alphanum values('A123'); SQL>insert into alphanum values('A234'); SQL>insert into alphanum values('A23'); SQL>insert into alphanum values('A3'); SQL>insert into alphanum values('A1'); SQL>-- Normal order [Numeric Off] SQL>select * from alphanum order by codes; CODES ========== A1 A123 A23 A234 A3 SQL>-- Numeric order [Numeric On] SQL>create collation numeric from eor using '[Numeric On]'; SQL>select * from alphanum order by codes collate numeric; CODES ========== A1 A3 A23 A123 A234