erDiagram
    EVENT_BOOKING }o--|| EVENT_SCHEDULE : "is for (if meeting-related)"
    COURSE_BOOKING }o--|| ROOM : "occupies"
    COURSE_BOOKING }o--|| COURSE_SCHEDULE : "is for (if course-related)"
    COURSE ||--o{ COURSE_SCHEDULE : "has"
    EVENT_BOOKING }o--|| ROOM : "occupies"
    TEACHER }o--o{ COURSE: "teach in"
    COURSE ||--o{ PLANNED_IN : "is included in"
    STUDYPLAN ||--o{ PLANNED_IN : "consists of"
    STUDYPLAN }o--|| SEMESTER : "runs during"
    UNIT ||--o{ STUDYPLAN : "is composed of"

    COURSE_BOOKING {
        int schedule_id FK
        int room_id FK
        bool available
    }

    EVENT_SCHEDULE {
        int role_id FK
        string name
        date start_datetime
        date end_datetime
        string type
        string description
        bool available
        bool visible
        int status
    }


    ROOM {
        string name
        string capacity
        string type
        bool available
    }

    COURSE_SCHEDULE {
        int course_id FK
        date start_datetime
        date end_datetime
        string type
        bool available
    }
    
    COURSE {
        string code
        string name
        int credits
        string edu_url
        bool available
    }


    SEMESTER {
        string name
        string type
        date start_date
        date end_date
        bool available
    }

    UNIT {
        string name
        string code
        string promo
        string section
        bool available
    }

    TEACHER {
        string name
        string people_url
        bool available
    }

    EVENT_BOOKING {
        int schedule_id FK
        int room_id FK
        bool available
    }