[IQ] Which table design has the best performance for IQ ?

Hi experts,

Assuming there is  over 1 billion for this table (table 1):

Table Design 1

Day               Time Range     No. of visitors

20150101     0000-0100           100

20150101     0100-0200          200

20150101     0200-0300          400

etc...

Table Design 2

Day               0000-0100     0100-0200     0200-0300...etc

20150101     100                    200               400

etc...

Which table should have the optimal performance for IQ if we perform a query for simple listing / aggregation ?