Using the @AoH that I have (as it is), is there a way I can rewrite this line:
while (@age_ref = \$sth->fetchrow_array)
so that it replaces the age values in @AoH, maybe using similar principles to those which allow this to update the age values:
($age_ref0,$age_ref2) = (\$AoH[0]{age},\$AoH[2]{age});

If not, what's preventing this?

#!/usr/bin/env perl
use warnings;
use strict;
use feature qw{ say };

my @AoH = ( { age => \ do { my $tmp = 42 } },
            {},
            { age => \ do { my $mpt = 33 } } );

my @age_ref = \($AoH[0]{age}, $AoH[2]{age});

(${ $age_ref[0] }, ${ $age_ref[1] }) = (1, 2);

use Data::Dumper; print Dumper \@AoH;
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($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
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Thanks choroba,

Sorry I wasn't clearer about this, but instead of this kind of thing, which you're suggesting:

(${ $age_ref[0] }, ${ $age_ref[1] }) = (1, 2);
[download]

where I'd have to type out all the variables on the left, I was after something more flexible, i.e. something which can handle any number of variables.  To do this maybe the syntax would have to mention the array (@) itself on the left.

This is a bit (or even a byte) academic now, because LanX's suggestion of DBI's bind_col() seems to be working for me.  However, I'm not against academia, since it may be useful in the future, but if you don't have any quick & easy ideas, feel free to drop this now, because at least my current problem is sorted.