Cloud computing is a new model in which computing infrastructure resources are provided as a service over the internet. Data owners can outsource their data in the cloud and benefit from on-demand high quality services. However, because cloud services and data owners are not in the same trusted domain, the outsourced data may be at risk. Therefore, data security is of critical importance in such a scenario. As a solution to this problem, data owners encrypt data before sending it to the cloud to ensure data confidentiality and cloud services decrypt it when processing queries. Such a scenario is not a suitable solution to data warehouse because of the large mass of data that will be processed. For that, this paper proposes a new schema based on the sample privacy homomorphism presented in [1]. This new schema improves the security of data warehouse hosted in the cloud, reduces storage space and processes encrypted data with minimum time complexity.