Modificar un Rol

ALTER ROLE name[ [ WITH ] option [ ... ] ]
whereoption can be:
SUPERUSER | NOSUPERUSER
| CREATEDB | NOCREATEDB
| CREATEROLE | NOCREATEROLE
| CREATEUSER | NOCREATEUSER
| INHERIT | NOINHERIT
| LOGIN | NOLOGIN
| CONNECTION LIMIT connlimit
| [ ENCRYPTED | UNENCRYPTED ] PASSWORD 'password'
| VALID UNTIL 'timestamp'

ALTER ROLE name RENAME TO newname

ALTER ROLE name SET parameter{ TO | = } { value | DEFAULT }
ALTER ROLE name RESET parameter