Hi Ion,
> there seems to be an example in the archives
> https://www.postgresql.org/message-id/20180526150323.GB28324%40momjian.us
Many thanks ! I shall indeed go Read The Fine Manual now.
In case I might have further questions I would like to come back,
post my work and understanding, and ask for specific guidance on
the aspects I can't fully solve myself.
Thanks again,
Karsten