in reply to Multiple references pointing to the same memory location

I don't know of any other algorithm for that. However, I can offer a less verbose syntax.
foreach $key (@keys) { $sth->execute($key); $columns_ref=[@{$sth->fetchrow_arrayref()}]; push(@entries, $columns_ref); }
I'm not sure if that'll save you much in performance, but it does save screen space. (Plus it avoids a couple extra symbol table entries, which can't be a bad thing, right?)

=cut
--Brent Dax
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