Re: STOP all user access except for admin for a few minutes?

Thx Russel,
I want to control it from software, changing network access via pg_hba with
software doesnt feel right.

================ possible case================
Say I have a Group called Normal_Rights and one called Zero_Rights.

So dB runs as... Normal_Rights(User A, User B, User C, User D)
Then via sql, superuser REVOKEs those user rights and GRANTs them
Zero_Rights(User A, User B, User C, User D)... ie make users a member of the
ZERO rights group.

Then hopefully Postgres kicks them out gracefully?????

Then software make changes and switch's them back to their Normal_Rights
group.

================ or more general case================
RECORD all the SQL for all user rights...
REVOKE everything except needed software superusers (postgres, and program
superuser).
make changes via software.
PLAY BACK all the rights SQL script.

What do you think, will PG kill connections, let them go gracefully, stop
after current transaction????

================ maybe I'm in the wrong tree================
Is it possible to make quick structural changes to postgres, with user
activety?
Maybe start a transaction that changes structure... wonder if that will stop
or hold user activity???

Thx
.