看闪回恢复区空间使用情况

查询Oracle闪回区路径及闪回区目录大小

(1) 查看闪回区是否开启
SQL> select flashback_on from v$database

(2) 查看闪回区大小
SQL> show parameter retention

NAME				     TYPE	 VALUE
------------------------------------ ----------- ------------------------------
db_flashback_retention_target	     integer	 1440
undo_retention			     integer	 36000

SQL>  show parameter db_recover

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest                string      /u01/app/oracle/fast_recovery_
                                                 area
db_recovery_file_dest_size           big integer 4560M

(3) 查看闪回区使用情况
SQL>  select * from v$flash_recovery_area_usage;

(4) 修改闪回区大小
alter system set db_recovery_file_dest_size = 20G;