oracle学习笔记07_Maintaining the Control File
--------
Oracle strongly recommends that your database has a minimum of two
control files and that they are located on separate physical
disks.
--------Control File Contents
Database name and identifier
Time stamp of database creation
Tablespace names
Names and locations of data files and online redo log files
Current online redo log file sequence number
Checkpoint information
Begin and end of undo segments
Redo log archive information
Backup information
--------增加control file：Using spfile
第一步：alter system set control_files=
'$HOME/ORADATA/u01/ctrl01.ctl','$HOME/ORADATA/u02/ctrl02.ctl' scope=spfile
第二步：关闭数据库
第三步：拷贝控制文件到新加的控制文件
第四步：重启数据库
--------Get control file Info
V$controlfile
v$parameter
v$controlfile_recore_section
总结：oracle的control file至少需要两个，分别放到不同的磁盘里（应对单点故障，提高安全性）
