URLID   HOSTID
1   1
2   1
2   1
2   1
3   1
3   1
4   1
5   1
5   1
5   1
5   1
6   2
6   2
7   2
8   2
8   2
8   2
9   3
9   3
10  3
11  3
11  3
11  3
12  3

values returned should be
HOSTID  URLID   COUNT
1   5   11
3   11  7
2   8   6

Explination:
HOSTID=1 is most common HOSTID. 5 is the most common URLID with HOSTID=1, and there are 11 total HOSTID=1's
HOSTID=3 is second most common HOSTID. 11 is the most common URLID with HOSTID=3, and there are 7 total HOSTID=3's
so on