"David G. Johnston" <david.g.johnston@gmail.com> writes:
> On Wed, Nov 9, 2022 at 1:54 PM Ron <ronljohnsonjr@gmail.com> wrote:
>> But this raises a different question: when does the postgres database not
>> exist?
> You are giving it too much specialness. Both ALTER DATABASE ... RENAME and
> DROP DATABASE can be used on it.
The template databases aren't all that special either. There is a defense
against dropping them accidentally:
regression=# drop database template1;
ERROR: cannot drop a template database
but you can override that if you really mean it:
regression=# alter database template1 with is_template false;
ALTER DATABASE
regression=# drop database template1;
DROP DATABASE
This might seem pretty scary, but it's intentional, per the comments
in IsPinnedObject:
* Databases are never pinned. It might seem that it'd be prudent to pin
* at least template0; but we do this intentionally so that template0 and
* template1 can be rebuilt from each other, thus letting them serve as
* mutual backups (as long as you've not modified template1, anyway).
regards, tom lane