$query = "SELECT distinct date, priceInCents FROM META_VAL WHERE date >= DATE_SUB(NOW(), INTERVAL 7 DAY) ORDER BY date ASC";
$sth = $dbh->prepare($query);
$sth->execute or die "SQL Error: $DBI::errstr\n";

while (my @result = $sth->fetchrow_array) {
    push @dates,  $result[0];
    push @prices, ($result[1]/100);
}

my $mygraph = Chart::Gnuplot->new(
    output       => "chart.png",
    timeaxis     => 'x',
    xlabel       => 'Date',
    ylabel       => 'Price',
}
my $data = Chart::Gnuplot::DataSet->new(
    xdata   => \@dates,
    ydata   => \@prices,
    style   => 'linespoints',
    timefmt => '%Y-%m-%d $H:%M:%S',      # input time format
);
$mygraph->plot2d($data);