How is primary key tied to document title?

Hi everyone. I'm currently transferring a lot of items from another tool to siyuan and there is one thing I don't understand regarding databases.

In a lot of cases my goal is to have documents as database entries that then have database properties.

When the document title changes, the primary key should change too,

Test 1 (works as intended)

Changing the page title

To reproduce, create a new page out of a primary key via "more" -> "New Doc"

Change title of the "Entry Three" in the document directly

this will trigger a change in the database primary key

Works like I expected.

Test 2 (behavior I don't understand)

Changing the primary key text in the database

When I change the primary key text in the database, it won't update the page title.

and the "reverse connection" (changing the document title) doesn't change the database entry title anymore.

Which makes it so that if I wanted to change it again, I always have to change it at two places.

My workaround is to never try to change the primary key directly. I'm not sure if this is an intended bahavior, so I'm posting it here as a question.