== ER Diagram ==

[[Image(tastytabs-er.png)]]

=== Entities ===

 * **Entity: User**  
   * **Description**: Contains main information about all users in the system.  
   * **Primary Key**: `id`.  
   * **Attributes**:  
     * **email**: User's email address.  
     * **street**: Street address of the user.  
     * **city**: City of residence.  
     * **phone_number**: Contact phone number.  
     * **password**: Encrypted user password.  

 * **Entity: Employee**  
   * **Description**: Represents employees of the system.  
   * **Primary Key**: `id`.  
   * **Attributes**:  
     * **user_id**: Foreign key referencing `User`.  
     * **net_salary**: The net salary of the employee.  
     * **gross_salary**: The gross salary of the employee.  

 * **Entity: Customer**  
   * **Description**: Represents customers in the system.  
   * **Primary Key**: `id`.  
   * **Attributes**:  
     * **user_id**: Foreign key referencing `User`.  

 * **Entity: Manager**  
   * **Description**: A disjoint specialization of the `Employee` entity for managers.  
   * **Primary Key**: `employee_id`.  

 * **Entity: FrontStaff**  
   * **Description**: A disjoint specialization of the `Employee` entity for front-facing staff members.  
   * **Primary Key**: `employee_id`.  
   * **Attributes**:  
     * **tip_percent**: Percentage of tips allocated to the staff.  
     * **staff_role_id**: Foreign key referencing `StaffRole`.  

 * **Entity: BackStaff**  
   * **Description**: A disjoint specialization of the `Employee` entity for back-office staff members.  
   * **Primary Key**: `employee_id`.  
   * **Attributes**:  
     * **staff_role_id**: Foreign key referencing `StaffRole`.  

 * **Entity: StaffRole**  
   * **Description**: Defines roles for staff members.  
   * **Primary Key**: `id`.  
   * **Attributes**:  
     * **name**: Name of the staff role.


 * **Entity: Shift**  
   * **Description**: Represents a work shift in the system.  
   * **Primary Key**: `id`.  
   * **Attributes**:  
     * **date**: Date of the shift.  
     * **start**: Start time of the shift.  
     * **end**: End time of the shift.
     * **employee_id**: Foreign key referencing `Manager`.

 * **Entity: Assignment**  
   * **Description**: Represents shift assignment for each employee.  
   * **Primary Key**: `id`.  
   * **Attributes**:  
     * **clock_in_time**: Clock in time of the employee.  
     * **clock_out_time**: Clock out time of the employee. 
     * **manager_id**: Foreign key referencing `Manager`.
     * **employee_id**: Foreign key referencing `Employee`.
     * **shift_id**: Foreign key referencing `Shift`.
   

 

 * **Entity: Reservation**  
   * **Description**: Represents reservations made by users.  
   * **Primary Key**: `id`.  
   * **Attributes**:  
     * **stay_length**: Duration of the stay.  
     * **datetime**: Date and time of the reservation.  
     * **creation_timestamp**: Timestamp when the reservation was created.  
     * **number_of_people**: Number of people in the reservation.  
     * **customer_id**: Foreign key referencing `Customer`.  


 * **Entity: Category**  
   * **Description**: Represents product categories.  
   * **Primary Key**: `id`.  
   * **Attributes**:  
     * **name**: Name of the category.  
     * **is_available**: Availability status of the category.  

 * **Entity: Product**  
   * **Description**: Represents items that can be purchased in the system.  
   * **Primary Key**: `id`.  
   * **Attributes**:  
     * **name**: Name of the product.  
     * **price**: Price of the product.  
     * **tax_class**: Tax classification for the product.  
     * **description**: Description of the product.  
     * **category_id**: Foreign key referencing `Category`.  
     * **manage_inventory**: Boolean indicating if inventory is managed.  

 * **Entity: Inventory**  
   * **Description**: Tracks product quantities and restocking levels.  
   * **Primary Key**: `product_id`.
   * **Attributes**:  
     * **quantity**: Current stock quantity.  
     * **restock_level**: Minimum stock level before restocking is required.  

 * **Entity: OrderItem**  
   * **Description**: Represents items in a customer's order.  
   * **Primary Key**: `id`.  
   * **Attributes**:  
     * **quantity**: Quantity of the product ordered.  
     * **price**: Price of the product in the order.  
     * **is_processed**: Processing status of the item.  
     * **timestamp**: Time when the item was added.  
     * **product_id**: Foreign key referencing `Product`.  
     * **order_id**: Foreign key referencing `Order`.  

 * **Entity: Order**  
   * **Description**: Represents a customer's order in the system.  
   * **Primary Key**: `id`.  
   * **Attributes**:  
     * **timestamp**: Time when the order was placed.  
     * **status**: Status of the order.  
     * **employee_id**: Foreign key referencing `Employee`.  

 * **Entity: TabOrder**  
   * **Description**: Represents orders made at a specific table.  
   * **Primary Key**: `order_id`.  
   * **Attributes**:  
     * **table_number**: Foreign key referencing `Table`.   

 * **Entity: OnlineOrder**  
   * **Description**: Represents orders made online by customers.  
   * **Primary Key**: `order_id`.  
   * **Attributes**:  
     * **customer_id**: Foreign key referencing `Customer`.  

 * **Entity: Table**  
   * **Description**: Represents dining tables in the system.  
   * **Primary Key**: `table_number`.  
   * **Attributes**:  
     * **seat_capacity**: Seating capacity of the table.  

 * **Entity: Payment**  
   * **Description**: Represents payments for orders.  
   * **Primary Key**: `id`.  
   * **Attributes**:  
     * **tip_amount**: Amount of tip included.  
     * **timestamp**: Time of payment.  
     * **payment_type**: Type of payment (e.g., cash, card).  
     * **amount**: Total payment amount.  
     * **order_id**: Foreign key referencing `Order`.  


=== Relationships ===

 * **belongs_to** 1:N Relation between `Category` and `Product`.
   * Description: Indicates which category a product belongs to.

 * **is_in**: 1:1 Relation between `Product` and `Inventory`.
   * Description: Indicates the product's record in inventory.

 * **is**: 1:N Relation between `Product` and `OrderItem`.
   * Description: Indicates which products are order items.

 * **has**: 1:M Relation between `Order` and `OrderItem`.
   * Description: Indicates which order items belong to a given order.

 * **places_order**: 1:P Relation between `Customer` and `OnlineOrder`.
   * Description: Indicates which online order a customer placed.

 * **is_placed_on**: 1:M Relation between `Table` and `TabOrder`.
   * Description: Indicates which table a tab order is placed on.

 * **has_payment**: 1:1 Relation between `Order` and `Payment`.
   * Description: Indicates the payment for the given order.

 * **creates**: 1:M Relation between `Manager` and `Shift`.
   * Description: Indicates the manager's created shifts.

 * **assigns**: 1:N Relation between `Manager`, and `Assignment`.
   * Description: Indicates a manager making an assignment.

 * **assigned_to**: 1:N Relation between `Employee`, and `Assignment`.
   * Description: Indicates which employee has the assignment.

 * **is_assigned**: 1:N Relation between `Shift`, and `Assignment`.
   * Description: Indicates which shift is assigned.

 * **makes**: 1:P Relation between `Customer` and `Reservation`.
   * Description: Indicates which customer makes the reservation.

 * **has_role**: 1:N Relation between `StaffRole` and `BackStaff`/`FrontStaff`.
   * Description: Indicates the role of back-staff/front-staff employees.