问题背景:
测试数据库执行shutdown immediate，日志里面报错，错误信息为：ORA-19815: WARNING: db_recovery_file_dest_size of 4322230272 bytes is 99.77% used, and has 9814016 remaining bytes available.
随即我执行startup force mount将数据库强制关闭并启动到mount状态，通过RMAN把历史备份和归档信息都删除后启动数据库报错ORA-38760.
问题现象：
SQL> startup mount;
Oracle instance started.
Total System Global Area 2872786944 bytes
Fixed Size 2256712 bytes
Variable Size 2634023096 bytes
Database Buffers 218103808 bytes
Redo Buffers 18403328 bytes
Database mounted.
SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-38760: This database instance failed to turn on flashback database
问题分析：
该错误通过查看Metalink 后得知是因为Flash back信息不完整导致。
[oracle@db01 ~]$ oerr or 38760
oerr: Unknown facility 'or'
[oracle@db01 ~]$ oerr ora 38760
38760, 00000, "This database instance failed to turn on flashback database"
// *Cause: Database flashback is on but this instance failed to
// start generating flashback data. Look in alert log for more
// specific errors.
// *Action: Correct the error or turn off database flashback.
解决办法：
#1、关闭flash backup再open database
SQL> alter database flashback off;
SQL> alter database open;
#2、另外一种办法直接关闭数据库后再启动也是可以的
SQL> startup force mount;
ORACLE instance started.
Total System Global Area 2872786944 bytes
Fixed Size 2256712 bytes
Variable Size 2634023096 bytes
Database Buffers 218103808 bytes
Redo Buffers 18403328 bytes
Database mounted.
SQL> alter database open;
Database altered.
SQL>
--------------------------------------分割线 --------------------------------------
Oracle 11g 在RedHat Linux 5.8_x64平台的安装手册
Linux-6-64下安装Oracle 12C笔记
在CentOS 6.4下安装Oracle 11gR2(x64)
Oracle 11gR2 在VMWare虚拟机中安装步骤
Debian 下 安装 Oracle 11g XE R2
--------------------------------------分割线 --------------------------------------
：