ORA-01146: cannot start online backup

问题：

Error: [1146] ORA-01146: cannot start online backup - file 1 is already in backup

ORA-01110: data file 1: 'C:ORACLEORADATAORCL8SYSTEM01.DBF'

以上问题是指，system这个表空间现在是备份状态

解决：

alter tablespace system end backup;