This is the roof top of Jewel Box but best time to visit was in the morning or night cause it could be very hot on the roof top in the afternoon. But you could visit some of the air conditioned restaurants located on the lower floor where you could dine or have a drink and a good view of Singapore.
Some cable cars used as deco. for the roof top pub.
You could follow what this family did, hide in the shelter from the hot sun and bring their own drinks and food. The rooftop pub is not open during the daytime except for the restaurants which are open for lunch and dinner.