Oracle12C查询自建用户（非系统自带）

select username from dba_users where INHERITED='NO';

 或者

SELECT username,account_status from dba_users where account_status = 'OPEN' and username not like '%SYS%' and username not like 'C##%' and username not like 'PDBADMIN' and username not like 'DBSNMP';