Re: SQL command : ALTER DATABASE OWNER TO

Agreed, and I do recall that - it is documented on the GRANT page.  Also noted is I can "inherit ownership" if I exercise that inherited ability the resultant grant still comes from the owner.  This unifies two of three ways for these grants to be established.

If I give out the ability via a grant option only then does the grantor become the grant optioned role.  This is the expected behavior and doesn't require documentation explicitly.

The following testing of this behavior surprises me though:

List of databases
-[ RECORD 1 ]-----+------------------------
Name              | newdb2
Owner             | testowner
Encoding          | UTF8
Locale Provider   | libc
Collate           | en_US.UTF-8
Ctype             | en_US.UTF-8
ICU Locale        |
ICU Rules         |
Access privileges | testowner=CTc/testowner+
                  | to3=C*T*c*/testowner   +
                  | to4=CTc/to3            +
                  | testowner=CTc/to3

postgres=> reset role;
RESET
postgres=# alter database newdb2 owner to davidj;
ALTER DATABASE
postgres=# \l newdb2
List of databases
-[ RECORD 1 ]-----+------------------
Name              | newdb2
Owner             | davidj
Encoding          | UTF8
Locale Provider   | libc
Collate           | en_US.UTF-8
Ctype             | en_US.UTF-8
ICU Locale        |
ICU Rules         |
Access privileges | davidj=CTc/davidj+
                  | to3=C*T*c*/davidj+
                  | to4=CTc/to3      +
                  | davidj=CTc/to3

I was expecting the privileges given to me by to3 to remain in place even after I lost my ownership grants.

As you've noted it seems unlikely this is something we are willing to change at this point.  So, in short, it seems impossible for an owner of an object to be left with any direct permissions on said object after having their ownership reassigned.  The role which gets the new assignment assumes all of the explicit grants that exist for the old role.

postgres=# alter database newdb2 owner to to3;
ALTER DATABASE
postgres=# \l newdb2
List of databases
-[ RECORD 1 ]-----+---------------
Name              | newdb2
Owner             | to3
Encoding          | UTF8
Locale Provider   | libc
Collate           | en_US.UTF-8
Ctype             | en_US.UTF-8
ICU Locale        |
ICU Rules         |
Access privileges | to3=C*T*c*/to3+
                  | to4=CTc/to3

This makes sense since the three grants that to3 would have after merging are consolidated into a single one - in an additive sense and the grant options being retained if present.

David J.