Cloud computing has many providers and it is supported on the large scale. The providers with their databases are as follows:

• Google bigtable: it is a hybrid cloud that consists of a big table that is spilt into tables and rows. MapReduce is used for modifying and generating the data.

• Amazon SimpleDB: is a webservice that is used for indexing and querying the data. It allows the storing, processing and creating query on the data set within the cloud platform. It has a system that automatically indexes the data.

• Cloud based SQL: is introduced by Microsoft and it is based on SQL database. it provides data storage by the usage of relational model in the cloud. The data can be accessed from the cloud using the client application.