bedidentityModel

Data model description

in the simple model, we want to track free beds on a by-station basis. For this, each station belongs to a hospital (many-to-one relationship) and each station has multiple bed counts (one-to-many relationship). Furthermore, each bed count has exactly one bed type related, but one bed type can be related to multiple bed counts. Below, we will discuss each of the aforementioned data types in detail. Each data type entity is identified by a randomly generated type 4 UUID, which is also the primary key in the corresponding table.

Hospital data type

table name: hospital

Fields:

• id: the unique UUID.
• name: the name of the hospital, as VARCHAR (255) NOT NULL.
• max_capacity: the maximum bed capacity (accumulated) of a hospital, represented as SMALLINT NOT NULL and should always be > 0.
• lat: the String-representation of the geolocation latitude, represented as VARCHAR (255). Should be nullable to allow for missing data.
• long: the String-representation of the geolocation longitude, represented as VARCHAR (255). Should be nullable to allow for missing data.

Station type data type

table name: station_type

Fields:

• id: the unique UUID.
• name: the name station type, as VARCHAR (255) NOT NULL.

Implementation remark:

This should be implemented as enum in the business logic. A station_type with name UNKNOWN should be implemented.

Station data type

table name: station

Fields:

• id: the unique UUID.
• name: the name of the station, as VARCHAR (255) NOT NULL.
• hospital_id: the foreign key to the corresponding hospital. This database column should be indexed. Not nullable.
• station_type_id: the foreign key to the corresponding station_type. This database column should be indexed. Not nullable.

bed type data type

table name: bed_type

Fields:

• id: the unique UUID
• name: the name of the bed type, as VARCHAR (255) NOT NULL. This database column should be indexed.

Implementation remark:

This should be implemented as enum in the business logic.

Bed type count data type

table name: bed_type_count

Fields:

• id: the unique UUID.
• max_capacity: the maximum bed count (accumulated) of this type in the corresponding station, represented as SMALLINT NOT NULL and should always be > 0.
• current_occupied: the number of currently occupied beds (accumulated) of this type in the corresponding station, represented as SMALLINT NOT NULL and should always be >= 0 and <= max_count.
• occupied_last_changed: the UNIX-timestamp when the current_occupied attribute was last changed as BIGINT NOT NULL DEFAULT EXTRACT(EPOCH FROM NOW() * 1000).
• station_id: the foreign key to the corresponding station. This database column should be indexed. Not nullable.
• bed_type_id: the foreign key to the corresponding bed_type. This database column should be indexed. Not nullable.

Implementation detail:

The occupied_last_changed must always be updated when current_occupied is changed.