Implementing Multi-Tenancy

spring.jpa.properties.hibernate.multiTenancy=SCHEMA
spring.jpa.properties.hibernate.tenant_identifier_resolver=com.acme.TenantResolver
spring.jpa.properties.hibernate.multi_tenant_connection_provider=com.acme.SchemaProvider

ALTER TABLE orders ENABLE ROW LEVEL SECURITY;
CREATE POLICY tenant_isolation ON orders
  USING (tenant_id = current_setting('app.tenant_id')::uuid);
-- App sets per request:
SET LOCAL app.tenant_id = 'a1b2...';

public class TenantHolder {
    private static final ThreadLocal<UUID> CURRENT = new ThreadLocal<>();
    public static void set(UUID id) { CURRENT.set(id); }
    public static UUID get() { return CURRENT.get(); }
    public static void clear() { CURRENT.remove(); }
}