I'm new to Multi Tenant Apps now I am exploring to to partition data based on Tenant id as far as I seen all Entity have @TenantId as string like this:

@Entity
public class Table {
    @TenantId
    private String tenant;
}

Can we have it as Tenant object it self like:

@Entity
public class Tenant {
    @Column(nullable = false)
    @Id
    @GeneratedValue(strategy = GenerationType.UUID)
    private String id;
}

And:

@Entity
public class Table {
    @TenantId
    @ManyToOne
    @JoinColumn(name = "tenant_id", nullable = false)
    private Tenant tenant;
}

Since I want to delete all tenant related rows when an tenant gets deleted is there any way to do it? Also It is not necessary to have tenant object itself in every entity (except some) mostly I don't need except for partitioning so even adding foreign key to it may be enough. How to do it? is there anything I'm missing?

I'm new to Multi Tenant Apps now I am exploring to to partition data based on Tenant id as far as I seen all Entity have @TenantId as string like this:

@Entity
public class Table {
    @TenantId
    private String tenant;
}

Can we have it as Tenant object it self like:

@Entity
public class Tenant {
    @Column(nullable = false)
    @Id
    @GeneratedValue(strategy = GenerationType.UUID)
    private String id;
}

And:

@Entity
public class Table {
    @TenantId
    @ManyToOne
    @JoinColumn(name = "tenant_id", nullable = false)
    private Tenant tenant;
}

Since I want to delete all tenant related rows when an tenant gets deleted is there any way to do it? Also It is not necessary to have tenant object itself in every entity (except some) mostly I don't need except for partitioning so even adding foreign key to it may be enough. How to do it? is there anything I'm missing?

• java
• spring-boot
• hibernate

1 Answer 1

There are few strategies for Multiple-tenant with Spring Boot and Hibernate tenant feature.

You follow the strategy what temporary (Spring team) called "partitioned table" as see at https://spring.io/blog/2022/07/31/how-to-integrate-hibernates-multitenant-feature-with-spring-data-jpa-in-a-spring-boot-application#example-1-partitioned-data . In this strategy, tenantId put inside per table.

You want

want to delete all tenant related rows when an tenant gets deleted

The key point at

@Autowired
TenantIdentifierResolver currentTenant;

in this file

@SpringBootTest
@TestExecutionListeners(listeners = {DependencyInjectionTestExecutionListener.class})
class ApplicationTests {

    static final String PIVOTAL = "PIVOTAL";
    static final String VMWARE = "VMWARE";

    @Autowired
    Persons persons;

    @Autowired
    TransactionTemplate txTemplate;

    @Autowired
    TenantIdentifierResolver currentTenant;

    @Test
    void saveAndLoadPerson() {

        Person adam = createPerson(PIVOTAL, "Adam");
        Person eve = createPerson(VMWARE, "Eve");

        assertThat(adam.getTenant()).isEqualTo(PIVOTAL);
        assertThat(eve.getTenant()).isEqualTo(VMWARE);

        currentTenant.setCurrentTenant(VMWARE);
        assertThat(persons.findAll()).extracting(Person::getName).containsExactly("Eve");

        currentTenant.setCurrentTenant(PIVOTAL);
        assertThat(persons.findAll()).extracting(Person::getName).containsExactly("Adam");
    }

    private Person createPerson(String schema, String name) {

        currentTenant.setCurrentTenant(schema);

        Person adam = txTemplate.execute(tx ->
                {
                    Person person = Persons.named(name);
                    return persons.save(person);
                }
        );

        assertThat(adam.getId()).isNotNull();
        return adam;
    }
}

source: https://spring.io/blog/2022/07/31/how-to-integrate-hibernates-multitenant-feature-with-spring-data-jpa-in-a-spring-boot-application#example-1-partitioned-data

You must: Delete all rows what related to tenant first. Then delete tenant (a small number of tenant, you can delete manually).

For simple, you can use SQL queries for deleting, it is easiest way.

DELETE FROM foo where tenantId = 'd3dd94d7-9603-441c-90dc-af87e6f3f8c9'
DELETE FROM bar where tenantId = 'd3dd94d7-9603-441c-90dc-af87e6f3f8c9'

or by source code, you create an REST endpoint, where passed to UUID tenant_id, then trigger/call repositories's method for deleting (in correct order if you use many Foreign keys. For example, 1 department has many employees, you must delete employee table first, then delete department table later.