SQL documentation uses LEFT JOIN

Describe the issue

On the page https://www.kimai.org/documentation/sql-examples.html

it shows several SQL queries.

Here is one example:

SELECT
    c.name as Customer,
    u.username as Username,
    u.alias as User,
    FORMAT(SUM(t.duration) / 3600, 0) as Duration
FROM
    kimai2_timesheet t
        LEFT JOIN kimai2_projects p on t.project_id = p.id
        LEFT JOIN kimai2_customers c on p.customer_id = c.id
        LEFT JOIN kimai2_users u on t.user = u.id
GROUP BY
    c.id, t.user, c.name, u.username, u.alias
;

This shows LEFT JOIN on projects and users. But it also seems from the GUI that those are required fields. If that is case then these should instead be JOIN instead.

I already tried

[X] I've read and searched the documentation.
[X] I've searched for similar issues in this repository.
[X] I've searched for similar issues in the discussions.

Kimai version

How do you run Kimai?

KIMAI CLOUD

Which PHP version are you using?

8.1

Logfile

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