in reply to
How do you critique another person's code?
Since he's an new programmer, I would suggest going easy. I'm going to assume no one else he works with knows Perl at all, otherwise, they wouldn't be going to the DBA's (I don't know, but you may be at one of those places that blame everything on the DBA's). I guess the best things to suggest are the most basic things such as modularization of code, declaring variables (and using meaningful variable names), encouraging him to use the full power of the CGI module (by the way, if you really need a performance boost, mod_perl may not hurt either), etc.
Of course, make sure you present it in the proper manner. If you want to do a good job politically, start with the good things in the script. Then, go through the suggestions in a non-threatening manner, suggesting changes rather than starting with "This stinks!"
Hope this helps.