摘要：Abstract The service which enables us to use computing as a service across a product is known as cloud computing. Nowadays the cloud computing paradigm has been receiving significant excitement and attention in technological sphere. Cloud computing shares different resources and information between different devices which are located in different places always based on internet connection. According to this, a cloud DBMS is a database management system which acts through cloud computing. It is worth mentioning that the number of these DBMS which act through cloud computing is expected to increase in the future. Based on related research and results, there is an increment of interest in outsourcing of DBMS tasks to third parties that can afford these tasks with low and cheap cost. In this paper, we discuss about DBMS as a cloud service, advantages and disadvantages, opportunities and limitations, and we focus on the way how to offer a cloud DBMS as one of the best services. We focus on three main characteristics of cloud computing which are considered as the most worried issues of cloud platform. We review cloud database challenges such as: internet speed, multi-tenancy, privacy and security. We also focus on the way how to opposite these challenges in order to provide a successful cloud database. At the end of this paper we explain a specific architecture of cloud DBMS which is known as SCALEDB. We focus on its layer which this architecture contains and the way how these layers works. We thus express the need for a new DBMS, designed specifically for cloud computing environments.
