erDiagram
    USER {
        int id PK
        string name
        string email
        string password
        int role_id FK
    }
    
    ROLE {
        int id PK
        string name
    }
    
    PERMISSION {
        int id PK
        string name
    }
    
    ROLE_PERMISSION {
        int role_id FK
        int permission_id FK
    }
    
    SETTING {
        int id PK
        int user_id FK
        json preferences
        string theme
    }

    CHIRP {
        int id PK
        string content
        int user_id FK
    }

    USER ||--o{ ROLE : "belongs to"
    ROLE ||--o{ USER : "has many"
    USER ||--o{ CHIRP : "has many"
    CHIRP ||--o{ USER : "belongs to"
    ROLE ||--o{ ROLE_PERMISSION : "has many"
    PERMISSION ||--o{ ROLE_PERMISSION : "has many"
    ROLE_PERMISSION }o--|| ROLE : "belongs to"
    ROLE_PERMISSION }o--|| PERMISSION : "belongs to"
    USER ||--|| SETTING : "has one"
    SETTING ||--|| USER : "belongs to"