Exercise 9: Music Festival

erDiagram
  performer {
    string name
    string genre
    datetime birth_date
    int key PK "id_performer"
  }

  time_units {
    string name
    string label
    string uuid
    int key PK "id_time_units"
  }

    festival {
      string title
      datetime start_date
      datetime end_date
      decimal budget
      decimal total_cost
      string location
      int key PK "id_festival"
      int id_performer FK "id_performer"
      int id_festival_state FK "id_festival_state"
    }

    performer_festival {
      int duration
      decimal cost
      datetime moment_of_performance
      int key PK "id_performer_festival"
      int id_festival FK "id_festival"
      int id_performer FK "id_performer"
      int id_time_units FK "id_time_units"
    }

     customer {
        string name
        string phone
        string email
        decimal total_tax
        int key PK "id_customer"
    }

    ticket {
      string number
      decimal price
      datetime purchase_date
      int key PK "id_ticket"
      int id_festival FK "id_festival"
      int id_customer FK "id_customer"
    }

    festival_state {
      string name
      string label
      string uuid
      int key PK "id_festival_state"
    }

    performer_festival one--many festival : has
    time_units one--many performer_festival: has
    performer_festival one--many performer : has
    festival_state one--many festival : has
    festival one--many ticket: has
    customer one--many ticket: buy

Description #

• The property “name” in the table “performance_state” can have the values: “Scheduled”, “Ongoing”, “Completed” and “Canceled”.

• The property “name” in the table “time_units” can have the values: “Minutes” and “Hours”.

• In entities “time_units” and “performance_state”, name represents the state that will be displayed on the screen, label represents the value that programmer will use to filter the states, and the uuid represents a value to distinguish the states.

• A performer performs at a festival in the time interval “start_date” and “end_date” of the festival.

• The value of the field “total_cost” from the entity “festival” is the sum of the cost for every performer that performed in that festival.

• OBS: The value of the field “uuid” is generated automatically.

Tasks #

• performer/performer_festival/time_units/festival_state/festival/ticket/customer: Add, Edit, Delete.

  • When the performance is created, it will automatically become “Scheduled”.
  • The field “Festival state” from entity “festival” will be read-only in edit view.

• Create a catalog for entities: “festival_state”, “festival”, “performer”, “ticket”, “time_units”, and “customer”.

• Create event listeners for tables that needs validations (e.g., adding a performer without a name, festival without title, etc., should not be allowed).

• Check if the performer is occupied in the time interval of a festival (if he is at another festival in that interval), if he is → validation message.

  • To calculate when the performer ends his performance at a festival, use datetime→plusMinutes(dateStart, duration) and datetime→plusHours(dateStart, duration).

• Check if “total_cost” of the festival is higher than the sum of total tickets price and festival’s budget, if it is → validation message;

• Add an entity action at the fesival level “Start festival”:

  • First check if the festival has already been started (it already has the “Ongoing” state), if it was → validation message;
  • It will change the status from “Scheduled” → “Ongoing”;
  • A festival cannot start if it is in the “Canceled” or “Completed” state → validation message.

• Add a new entity action at the festival level “Cancel festival”:

  • It will change the festival status to “Canceled”;
  • A festival cannot be canceled if it is in the “Ongoing” or “Completed” state → validation message;
  • A festival cannot be canceled if it is already in the “Canceled” state → validation message.

• Add a new entity action at the festival level “Complete festival”:

  • It will change the festival status from “Ongoing” → “Completed”;
  • It can’t be completed if it has the status “Scheduled” or “Canceled” → validation message;
  • If it is already in “Completed” state → validation message.

• Performer report: festival situation at performer level (total number of festivals, ticket value).

• Ticket report: festival situation at ticket level (total number of festivals, ticket value, total number tickets).

• Customer report: total number of festivals, ticket value.