What kind of Oracle statement will list all roles and users

What kind of Oracle statement will list all roles and users (without repetition) who have access to a particular table?

Solution

SELECT DISTINCT A.GRANTED_ROLE,B.GRANTEE FROM DBA_ROLE_PRIVS A, DBA_TAB_PRIVS B
WHERE
A.GRANTEE=B.GRANTEE
AND B.TABLE_NAME=\'tablename\';

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