Yes, you most certainly can. IBM has a track record of mucking with things that didn't need mucking with.
The authoritative source for the use of a Perl distribution is the author's documentation, not a completely unaffiliated company.
I have had my software modified by a company in the past without any mention of the change, while leaving my contact information in the troubleshooting section. It was infuriating when I received a large number of email complaints that "your software doesn't work!".
Regardless of what it is, you're doing something wrong as your code isn't doing what you want, so leave IBM out of it, and refer to the proper documentation. That's your best bet to get back on track.
The authoritative methods you're looking for are:
fetchrow_arrayref() # fetch a single row, put it into an array referen
fetchrow_hashref() # fetch a single row, put it into a hash reference
fetchall_arrayref() # fetch all rows into an aref of arefs
fetchall_hashref() # fetch all rows into an href of hrefs