Evaluating Tenant Isolation Models
When engineering cloud-native Software-as-a-Service (SaaS) products, selecting the appropriate database partitioning strategy is one of the most critical early architectural decisions. The two primary paradigms are Single Database with Discriminator Columns (tenant_id) and Database-Per-Tenant.
Single Database with Tenant Scopes
For most mid-market SaaS platforms, maintaining a single relational database where tables include an indexed tenant_id column offers significant operational efficiency. With global Eloquent scopes automatically scoping queries, application code is shielded from cross-tenant data leaks while maintaining minimal infrastructure hosting costs.
Database-Per-Tenant for Enterprise Compliance
When serving healthcare or financial institutions with strict data residency mandates, separate tenant databases provide complete air-gapped isolation at the cost of higher migration orchestration complexity.