A Mixed Multi-tenancy Data Model and Its Migration Approach for the SaaS Application

Software providers exploit economies of scale by migrating traditional isolated tenancy hosted applications to multi-tenancy supporting ones in the Cloud. How to transform a single-tenancy database to multi-tenancy model plays a key role in the vast majority of migrated SaaS (Software as a Service) applications and it also determines the cost paid by the tenants. In this paper, to meet the tenants´ cost-saving expectation versus database performance requirement, a mixed multi-tenancy data model and its architecture generating a configurable multi-tenancy data model group are proposed based on three existing data models firstly. Then, due to the analysis on the challenges arising from such a data migration scenario, this paper describes the design and implementation of our migration approach that enables tenants enjoy customizability of different data models with security and scalability of database services. Finally, a real-world case study demonstrates how our data model and migration approach can be used in the SaaS migration.