selectall_arrayref

I need some help with the selectall_arrayref.

my $ary_ref  = $dbh->selectall_arrayref($sql,{ Slice => {} }); #maybe I 
should be using Slice in this case?

Is it possible to (using one DB call), have arr_ref's and hash_ref's for 
use in a CGI checkbox_group, like this?

my $names = do something to ary_ref to get another array ref of the id 
column
my $ids = do something else to ary_ref to get a hash ref to the name column

@h = checkbox_group(-name=>'selection',-values=>$ids, -labels=>$names);

Obviously, the -values array reference and -labels hash syntax are where 
I need help.

Could somebody please help me with the syntax required to make this work?

Thanks!