控制文件的备份有两种格式的备份，一种是文本格式的备份另一种是二进制格式的备份 备份文本格式 sqlgt; alterdatabase backup c
控制文件的备份有两种格式的备份，一种是文本格式的备份另一种是二进制格式的备份
备份文本格式
sql> alterdatabase backup controlfile to trace as '/bk/con.sql';
databasealtered.
备份二进制格式
sql> alterdatabase backup controlfile to trace as '/bk/con.ctl';
databasealtered.
----加上as字句是为了自定义存储的位置
noresetlog重建控制文件sql>!cp /etc/passwd /u01/tiger/oradata/orcl2/control01.ctl
sql> altersystem swirch logfile;
alter systemswirch logfile
             *
error at line 1:
ora-02065:illegal option for alter system
sql> altersystem switch logfile;
alter systemswitch logfile
             *
error at line 1:
ora-03113:end-of-file on communication channel
sql> conn /assysdba
connected to anidle instance.
sql> startup
oracle instancestarted.
total systemglobal area  314572800 bytes
fixed size                  1219136 bytes
variablesize             109053376 bytes
databasebuffers          197132288 bytes
redobuffers                7168000 bytes
ora-00205: errorin identifying control file, check alert log for more info
这里发现当mount的时候发现控制文件有问题，，这样我们可以根据之前备份的控制文件的文本文件来恢复控制文件
createcontrolfile reuse database orcl2 noresetlogs  archivelog
    maxlogfiles 16
   maxlogmembers 3
    maxdatafiles 100
    maxinstances 8
    maxloghistory 292
logfile
  group 1'/u01/tiger/oradata/orcl2/redo01.log' size 50m,
  group 2'/u01/tiger/oradata/orcl2/redo02.log' size 50m,
  group 3'/u01/tiger/oradata/orcl2/redo03.log'  size50m
datafile
  '/u01/tiger/oradata/orcl2/system01.dbf',
  '/u01/tiger/oradata/orcl2/tiger.dbf',
  '/u01/tiger/oradata/orcl2/sysaux01.dbf',
  '/u01/tiger/oradata/orcl2/users01.dbf',
  '/u01/tiger/oradata/orcl2/undotbs02.dbf',
  '/u01/tiger/oradata/orcl2/undotbs01',
  '/u01/tiger/oradata/orcl2/tiger01.dbf'
character setzhs16gbk
sql> alterdatabase open;
alter databaseopen
*
error at line 1:
ora-01113: file1 needs media recovery
ora-01110: datafile 1: '/u01/tiger/oradata/orcl2/system01.dbf'
sql> recoverdatabase;
media recoverycomplete.
sql> alterdatabase open;
databasealtered.