I have a problem to join 2 tables. It may deals with "full join" or "cross join", but I cannot make it...

Here is a simple example :
- 2014 : a client "Client 1" is coming to the company
- 2015 : his client\_id is changing (change appears in #client table)
- 2016 : he gets an Audi car (change appears in #car table)
- 2017 : he replaces his Audi by a BMW (change appears in #car table)

What I want is a query which gives me 4 rows with all the changes and the proper dates, like in this picture :

[![enter image description here](https://i.stack.imgur.com/UfMqm.png)](https://i.stack.imgur.com/UfMqm.png)

Just in case, here is the SQL code sample :

```
drop table #client
drop table #car

create table #client
(
       client_name varchar(64),
       client_id varchar(64),
       date_validity_start date,
       date_validity_end date
)

create table #car
(
       client_name varchar(64),
       car_brand varchar(64),
       date_validity_start date,
       date_validity_end date
)

insert into #client values('Client 1', 'A', '20140101', '20141231')
insert into #client values('Client 1', 'B', '20150101', '20991231')

insert into #car values('Client 1', 'Audi', '20160101', '20161231')
insert into #car values('Client 1', 'BMW', '20170101', '20991231')

```

Could you pleasy help me out ?
Thanks a lot !