执行备份命令
RMAN> BACKUP DATABASE;
Starting backup at 2021-04-25 16:26:17
using channel ORA_DISK_1
RMAN-06169: could not read file header for datafile 8 error reason 4
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of backup command at 04/25/2021 16:26:18
RMAN-06056: could not access datafile 8
select file#,name from v$datafile;
查看所属的表空间
select a.file#,a.name,b.name from v$datafile a,v$tablespace b where a.ts#=b.ts#;
删除表空间及数据
SQL> drop tablespace RMANTBS including contents and datafiles;
RMAN> BACKUP DATABASE;
Starting backup at 2021-04-25 17:26:31
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=262 device type=DISK
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00001 name=/u01/app/oracle/oradata/orcl/system01.dbf
input datafile file number=00002 name=/home/data/Local10racl2.dbf
input datafile file number=00003 name=/u01/app/oracle/oradata/orcl/sysaux01.dbf
input datafile file number=00004 name=/u01/app/oracle/oradata/orcl/undotbs01.dbf
input datafile file number=00005 name=/u01/app/oracle/product/12.2.0/db_1/dbs/d:dataLocal10racl.dbf
input datafile file number=00007 name=/u01/app/oracle/oradata/orcl/users01.dbf
channel ORA_DISK_1: starting piece 1 at 2021-04-25 17:26:33
channel ORA_DISK_1: finished piece 1 at 2021-04-25 17:28:31 with 2 copies and tag TAG20210425T172633
piece handle=/u01/app/oracle/product/12.2.0/db_1/dbs/0evt6om9_1_1 comment=NONE
piece handle=/u01/app/oracle/product/12.2.0/db_1/dbs/0evt6om9_1_2 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:01:58
Finished backup at 2021-04-25 17:28:31
Starting Control File and SPFILE Autobackup at 2021-04-25 17:28:31
piece handle=/u01/app/oracle/product/12.2.0/db_1/dbs/c-1570833465-20210425-01 comment=NONE
Finished Control File and SPFILE Autobackup at 2021-04-25 17:28:34
including contents and datafiles;
RMAN-06056: could not access datafile 8
原文：https://www.cnblogs.com/JIKes/p/14707441.html