Search notes:

Oracle: DBA_ROLES

dba_roles lists the available roles. 
select
  role,
  password_required,
  authentication_type,
  common,
  oracle_maintained
from
  dba_roles
order by
  oracle_maintained,
  role;
Github repository Oracle-Patterns, path: /Installed/data-dictionary/roles/show.sql

See also

dba_role_privs lists the users and roles to whom roles are granted.
dba_connect_role_grantees
The attribute ORACLE_MAINTAINED contains a Y if the corresponding role is maintained by Oracle.

Index

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