One field with multiple values?

All we need is an easy explanation of the problem, so here it is.

I know that what I’m asking can’t be done or shouldn’t be done, but I really don’t know how to do it. This is the problem:

2 tables:

 - Drivers (id_driver, name, etc...) 
 - Trucks (id_truck, model, id_driver,
   etc...)

The user will fill a form with the truck’s info, but a truck may have more than one driver, and thats my problem. I don’t know what to do there.

Thanks in advance.

How to solve :

I know you bored from this bug, So we are here to help you! Take a deep breath and look at the explanation of your problem. We have many solutions to this problem, But we recommend you to use the first method because it is tested & true method that will 100% work for you.

Method 1

This is likely to be a many to many relationship.

create table drivers (
  driver_id int primary key,
  ...
);

create table trucks (
  truck_id int primary key,
  ...
);

create table drivers_trucks (
  driver_id int references drivers(driver_id),
  truck_id int references trucks(truck_id),

  primary key (driver_id, truck_id)
);

Method 2

Swap the foreign key so that the Drivers table has id_truck. This way multiple drivers can be associated with the same truck.

Note: Use and implement method 1 because this method fully tested our system.
Thank you 🙂

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