alter TABLE telemetry
add defective boolean default false,
add defective_reason varchar(64);

alter TABLE telemetry_data ADD 
unit varchar (16);

create table units (
    unit varchar(16) not null,
    target_unit varchar(16) not null,
    multiplier double not null,
    primary key (unit)
);

insert into units (unit, target_unit, multiplier) 
values ('c_x100', 'c', 0.01);