问题：查询select * from v$database
提示：ORA-00942: 表或视图不存在

登录DBA用户授权视图给该用户
grant select on v$instance to user_name;
grant select on v$databaseto user_name;
出现错误提示：
ORA-02030: 只能从固定的表/视图查询

–解决方法：
SQL> select * from dba_synonyms t where t.synonym_name = upper(‘v$database’);

OWNER SYNONYM_NAME TABLE_OWNER TABLE_NAME DB_LINK

PUBLIC V$DATABASE SYS V_$DATABASE

SQL> grant select on V_$DATABASE to user01;

Grant succeeded