Oracle - Select where field has lowercase characters

Question

I have a table, users, in an Oracle 9.2.0.6 database. Two of the fields are varchar - last_name and first_name.

When rows are inserted into this table, the first name a

Answer 1

I think BQ's SQL and Justin's second SQL will work, because in this scenario:

first_name        last_name
----------        ---------
bob               johnson
Bob               Johnson
BOB               JOHNSON

I want my query to return the first 2 rows.

I just want to make sure that this will be an efficient query though - my table has 500 million rows in it.

When you say upper(first_name) != first_name, is "first_name" always pertaining to the current row that oracle is looking at? I was afraid to use this method at first because I was afraid I would end up joining this table to itself, but they way you both wrote the SQL it appears that the equality check is only operating on a row-by-row basis, which would work for me.