If in the future you decide to ditch fetchrow_hashref, you can always get the column names back using the {NAME} attribute of the statement handle:

 my $query = $dbh->prepare( $SQLstatement );
 $query->execute();
 print "Column names: ", join( ', ', @{ $query->{NAME} }, "\n",
       "As upper: ", join( ', ', @{ $query->{NAME_uc} }, "\n",
       "As lower: ", join( ', ', @{ $query->{NAME_lc} }, "\n";
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Chris
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