# Multi-tenant SaaS partitioning models for PostgreSQL
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The best method for accomplishing multi-tenancy depends on the requirements for your SaaS application. The following sections demonstrate partitioning models for successfully implementing multi-tenancy in PostgreSQL. 

**Note**  
    The models discussed in this section are applicable to both Amazon RDS for PostgreSQL and Aurora PostgreSQL-Compatible. References to *PostgreSQL* in this section apply to both services.

There are three high-level models that you can use in PostgreSQL for SaaS partitioning: silo, bridge, and pool. The following image summarizes the trade-offs between the silo and pool models. The bridge model is a hybrid of the silo and pool models.


| 
| 
| Partitioning model | Advantages | Disadvantages | 
| --- |--- |--- |
| **Silo** | Compliance alignment | Compromised agility | 
| No cross-tenant impact | No centralized management | 
| Tenant-level tuning | Deployment complexity | 
| Tenant-level availability | Cost | 
| **Pool** | Agility | Cross-tenant impact | 
| Cost optimization | Compliance challenges | 
| Centralized management | All or nothing availability | 
| Simplified deployment |   | 
| **Bridge** | Some compliance alignment | Some compliance challenges | 
| Agility | All or nothing availability (mostly) | 
| Cost optimization | Cross-tenant impact | 
| Centralized management | Deployment complexity | 

The following sections discuss each model in more detail.