Cloud computing has revolutionized the way computing infrastructure is abstracted and used. There is a proliferation of number of applications which leverage various cloud platforms, resulting in a tremendous increase in the scale of data generated as well as consumed by such applications. This paper reviews the features of Cloud computing and then gives a survey of different database architecture for cloud computing. Scalable database management systems are a crucial part of the cloud infrastructure which includes both update intensive workloads and decision support systems. The paper presents an organized picture of the challenges and open issues pertaining to database management systems in developing and deploying internet scale applications in the cloud environment.