my $hostmatch;
while( $row = $sth->fetchrow_hashref ) {
    if( $host eq $row->{host} ) {
        $hostmatch = 1;
    }
}

##</code><code>##

if( param('select') and param('select') !~ /\.\./ )
{
    my $data = ...
    ...
}

##</code><code>##

my $data;
if( param('select') and param('select') !~ /\.\./ )
{
    $data = ...
    ...
}