databaseGuide.txt

users:
CREATE TABLE users (
    id serial PRIMARY KEY,
    username varchar(255),
    email varchar (255),
    password varchar(255),
    created_at timestamp with time zone NOT NULL,
    updated_at timestamp with time zone NOT NULL
);

cylinders:
CREATE TABLE cylinders (
    id serial PRIMARY KEY,
    name varchar(255),
    weight_device_id varchar(255),
    pressure_device_id varchar(255),
    created_at timestamp with time zone NOT NULL,
    updated_at timestamp with time zone NOT NULL
);

cylinders_records:
CREATE TABLE cylinders_records (
    date timestamp with time zone NOT NULL,
    device_id varchar(255) NOT NULL,
    type varchar(255) NOT NULL,
    value float NOT NULL,
    cylinder_id int NOT NULL
);
ALTER TABLE cylinders_records
ADD CONSTRAINT fk_cylinder_id
FOREIGN KEY (cylinder_id)
REFERENCES cylinders (id)
ON UPDATE CASCADE
ON DELETE CASCADE;

users_cylinders:
CREATE TABLE users_cylinders (
    created_at timestamp with time zone NOT NULL,
    updated_at timestamp with time zone NOT NULL,
    user_id int NOT NULL,
    cylinder_id int NOT NULL 
);
ALTER TABLE users_cylinders
ADD CONSTRAINT fk_user_id
FOREIGN KEY (user_id)
REFERENCES users(id)
ON UPDATE CASCADE
ON DELETE CASCADE;
ALTER TABLE users_cylinders
ADD CONSTRAINT fk_cylinder_id
FOREIGN KEY (cylinder_id)
REFERENCES cylinders(id)
ON UPDATE CASCADE
ON DELETE CASCADE;