1、是否开启审计功能查询

show parameter audit

NAME                                 TYPE        VALUE

------------------------------------ ----------- ------------------------------
audit_file_dest                      string      /home/oracle/app/oracle/admin/
                                                 orcl/adump
audit_sys_operations                 boolean     FALSE
audit_syslog_level                   string
audit_trail                          string      DB

解释：false表示没有开启

2、开启审计功能

SQL> alter system set audit_sys_operations=TRUE scope=spfile;   

SQL> alter system set audit_trail=db,extended scope=spfile;

注：开启之后需要重启数据库