ERD — Multi-tenant SaaS

erDiagram
ORGANISATION ||--o{ MEMBERSHIP : has
USER         ||--o{ MEMBERSHIP : has
ORGANISATION ||--o{ PROJECT    : owns
PROJECT      ||--o{ TASK       : contains
USER         ||--o{ TASK       : assigned

ORGANISATION {
  uuid id PK
  text name
  timestamptz created_at
}
USER {
  uuid id PK
  text email UK
  text name
}
MEMBERSHIP {
  uuid org_id FK
  uuid user_id FK
  text role
}
PROJECT {
  uuid id PK
  uuid org_id FK
  text title
}
TASK {
  uuid id PK
  uuid project_id FK
  uuid assignee_id FK
  text title
  text status
}