Database Multi-Tenancy Architecture

Design a multi-tenant database architecture:

**Application Type:** {{APPLICATION_TYPE}}
**Number of Tenants:** {{TENANT_COUNT}}
**Data Isolation Requirements:** {{ISOLATION_REQUIREMENTS}}
**Tenant Data Size Variation:** {{SIZE_VARIATION}}
**Compliance Requirements:** {{COMPLIANCE}}
**Database System:** {{DATABASE_SYSTEM}}

Please provide:
1. Multi-tenancy model selection:
   - Separate databases
   - Shared database, separate schemas
   - Shared schema with tenant ID
2. Schema design with tenant isolation
3. Query patterns for tenant data access
4. Connection management strategy
5. Tenant onboarding automation
6. Data migration between tenants
7. Cross-tenant reporting (if needed)
8. Performance isolation strategies
9. Security and compliance measures
10. Scaling considerations per model