Database

Database

1. Building
2. Room
3. Sensor
4. Reading

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Building

Syntax	Data Type	Description
ID	Long	Primary Key
Name	String	Name of building

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Room

Syntax	Data Type	Description
ID	Long	Primary Key
Name	String	Name of building
BuildingId	Long	Foreign key of building

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Sensor

Syntax	Data Type	Description
ID	Long	Primary Key[IOT ID]
Description	String	Description of Device
RoomId	Long	Foreign key of Room

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Reading

Syntax	Data Type	Description
ID	Long	Primary Key
Date	Date	Date and time of reading
CO2	Int	CO2 reading
SensorId	Long	Foreign key of Sensor

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Note

Foreign keys are one to many in a tree stuct building ->> room ->> device ->> reading

example code for Sensor entity

how the parent is defined in code

@ManyToOne(fetch = FetchType.LAZY, optional = false)
@JsonBackReference
@Getter
@Setter
private Room room;

how the child is defined in code

@OneToMany(mappedBy = "sensor", cascade = CascadeType.ALL, fetch = FetchType.LAZY)
@JsonManagedReference
@Setter
private Set<Reading> readings;