Zhen Zhang’s research while affiliated with IBM and other places

A method, apparatus, and a computer program product for storing and accessing multi-tenancy data. The method includes the steps of: creating a plurality of table sets in one or more databases, wherein each table set is used to store data of a group of tenants selected from a plurality of tenants; accessing data of a tenant in a table set in response to receiving a data access request from the tenant; and recording relationships between the tenants and the table sets in a multi-tenancy metadata repository, wherein the step of accessing the data of the tenant comprises the steps of finding the table set by querying the metadata repository and accessing the data of the tenant in the table set based on the result received from the query of the metadata repository.

Multi-tenancy is one of key characteristics of the service oriented computing especially for Software as a Service (SaaS) to leverage economy of scale to drive down total cost of ownership for both service consumer and provider. This paper aims to study the technologies to build a cost-effective, secure and scalable multi-tenant infrastructure, especially in data tier. We first explore all the key implementation patterns of data tier multi-tenancy on aspects of isolation, security, customization & scalability etc. Furthermore, we mainly evaluate the performance of these design patterns on aspects of isolation and security via a series of experiments and simulations. This paper also identifies the potential performance bottlenecks, summarizes corresponding optimization approaches and best implementation practices for different multi-tenant business usage models.