dconf binary databse env

Hello and happy holidays,

https://developer.gnome.org/dconf/unstable/dconf-overview.html
"dconf can be configured to place its binary database in "

I try to use custom directory for the binary database for flatpaks so
they don't conflict for example with system installed applications (so
they have different settings)

What is the environment variable to point to the binary database directory to?

Thanks in advance.

Best regards
Damian