An Elastic Multi-tenant Database Schema for Software as a Service

Software as a Service (SaaS) is an online software delivery model which permits a third party provider offering software services to be used on-demand by tenants over the internet, instead of installing and maintaining them in their premises. Nowadays, more and more companies are offering their web-base business application by adopting this model. Multi-tenancy is the primary characteristic of SaaS, it allows SaaS vendors to run a single instance application which supports multiple tenants on the same hardware and software infrastructure. This application should be highly customizable to meet tenants´ expectations and business requirements. In this paper, we propose a novel customizable database design for multi-tenant applications. Our design introduces an Elastic Extension Tables (EET) which consists of Common Tenant Tables (CTT) and Virtual Extension Tables (VET). This design enables tenants to create their own elastic database schema during multi-tenant application run-time execution to satisfy their business needs.