$DBI->do("blah");
if ($DBI->err) {
   print "Error: ", $DBI->errstr, "\n"; 
}

##</code><code>##

foreach (@STRUCTURE) {
    push @list, "$_ = ?";
    push @vals, $impl->{$_}->{value};
}
my $string = join ",",@list;
$DBH->do(qq{
    UPDATE $TABLENAME SET $string WHERE $KEY=? LIMIT 1
}, undef, @vals, $keyval);