select m, p from various_joined_tables_and_views where u = N group by m, p, u
</code.

<p>The result looks like this:</p>

<code>
m1, p1
m1, p2
m1, p3
m2, p1
m2, p2
m3, p1
.
.
.
alot more

##</code><code>##

[[m1, [p1,p2,p3], [m2, [p1,p2]], [m1, [p1]]]

##</code><code>##

my @data;
my %mkts;
my ($m, $p);
$cursor->bind_col(1, \$m);
# this is in the hope that DBD::Oracle will actually implement
# bind types in the future -
# see http://rt.cpan.org/Public/Bug/Display.html?id=49818
# because I'd really like this column to be scalar that looks like an number
# rather than a string - as JSON::XS will write it as N instead of 'N'
$cursor->bind_col(2, \$p, {type => SQL_INTEGER});
while ($cursor->fetch) {
  if (exists($mkts{$m})) {
    foreach (@data) {
      if ($_->[0] == $m) {
        push @{$_->[1]}, $p + 0; # make it look like a integer - see above
        last;
      }
    }
  } else {
    $mkts{$m} = 1;
    my $n = @data;
    $data[$n][0] = $m;
    $data[$n][1] = [$p] + 0;
  }
}