public int compare(QueryMetaData o1, QueryMetaData o2)
		{
			long left = o1.sizeExpected > -1 ? o1.sizeExpected : 
						o1.sizeUB > -1 ? o1.sizeUB : o1.sizeLB;
			if (left == -1)
				return 0;
			long right = o2.sizeExpected > -1 ? o2.sizeExpected : 
						 o2.sizeUB > -1 ? o2.sizeUB : o2.sizeLB;
			if (right == -1 || left == right)
				return 0;
			else if (left > right)
				return 1;
			else
				return -1;				
		}