CREATE TABLE Device
(
    DeviceId bigint IDENTITY(1,1) CONSTRAINT PK_Device PRIMARY KEY,
    Name nvarchar(100) NOT NULL
)
CREATE TABLE Measurement
(
    MeasurementId bigint IDENTITY(1,1) CONSTRAINT PK_Measurement PRIMARY KEY,
    DeviceId bigint CONSTRAINT FK_Measurement_Device FOREIGN KEY(DeviceId)
                    REFERENCES dbo.Device (DeviceId) NOT NULL,
    Temperature decimal(18, 2) NOT NULL,
    Humidity decimal(18, 2) NOT NULL,
    CreatedOn datetime NOT NULL
)
GO
INSERT INTO Device (Name) VALUES ('My only device')
GO