Database Case Insensitive Index?

Question

I have a query where I am searching against a string:

SELECT county FROM city WHERE UPPER(name) = \'SAN FRANCISCO\';

Now, this works fine,

Answer 1

Short answer, no.

Long answer, yes if you're running on the mainframe, but you're not, so you have to use other trickery.

DB2 (as of DB2/LUW v8) now has generated columns so you can:

CREATE TABLE tbl (
    lname  VARCHAR(20),
    fname  VARCHAR(20),
    ulname VARCHAR(20) GENERATED ALWAYS AS UPPER(lname)
);

and then create an index on ulname. I'm not sure you're going to get it simpler than that.

Before that, you used to have to use a combination of insert and update triggers to ensure the ulname column was kept in sync, and this was a nightmare to maintain. Also, now that this functionality is part of the core DBMS, it's been highly optimized (it's much faster than the trigger-based solution) and doesn't get in the way of real user triggers, so no extra DB objects to maintain.

See here for details.