有些时候，我们要清理数据库时，想把数据库中所有非系统自带的用户全部删除，在12C以前，我们只能通过人肉的方式，从12C 开始，多了一个字段： ORACLE_MAINTAINED如果时系统自带的，该值为Y,否则为N 就很好办了，直接使用以下语句就可以找出系统自带的用户了。 select username,account_status,ORACLE_MAINTAINED from dba_users where ORACLE_MAINTAINED='Y'; SQL> r 1* SELECT username,account_status from dba_users where ORACLE_MAINTAINED='Y' USERNAME ACCOUNT_STATUS ------------------------------ -------------------------------- SYS OPEN SYSTEM OPEN XS$NULL EXPIRED & LOCKED OJVMSYS LOCKED LBACSYS LOCKED OUTLN LOCKED SYS$UMF LOCKED DBSNMP LOCKED APPQOSSYS LOCKED DBSFWUSER LOCKED GGSYS LOCKED ANONYMOUS EXPIRED & LOCKED CTXSYS EXPIRED & LOCKED DVF LOCKED DVSYS LOCKED GSMADMIN_INTERNAL LOCKED MDSYS LOCKED OLAPSYS LOCKED XDB LOCKED WMSYS LOCKED GSMCATUSER LOCKED MDDATA LOCKED REMOTE_SCHEDULER_AGENT LOCKED SYSBACKUP LOCKED GSMUSER LOCKED GSMROOTUSER LOCKED SYSRAC LOCKED SI_INFORMTN_SCHEMA LOCKED AUDSYS LOCKED DIP LOCKED ORDPLUGINS LOCKED ORDDATA LOCKED SYSKM LOCKED ORACLE_OCM LOCKED ORDSYS LOCKED SYSDG LOCKED 36 rows selected.