select * from dba_objects where object_type=‘SCH’;

select
        ur.name,
        sch.name
from
        sysobjects sch,
        sysobjects ur
where
        ur.subtype$='USER'
    and sch.type$  ='SCH'
    and ur.name not like 'SYS%'
    and sch.pid=ur.id order by 1;

这个sql可以查看所有用户和每个用户对应的schema