#  使用alter database backup controlfile to trace;产生控制文件的trace file
-- Below are two sets of SQL statements, each of which creates a new
-- control file and uses it to open the database. The first set opens
-- the database with the NORESETLOGS option and should be used only if
-- the current versions of all online logs are available. The second
-- set opens the database with the RESETLOGS option and should be used
-- if online logs are unavailable.
-- The appropriate set of statements can be copied from the trace into
-- a script file, edited as necessary, and executed when there is a
-- need to re-create the control file.
#  需要重建控制文件的话， 如果online redo 是可用的, 使用NORESETLOGS 创建新控制文件打开数据库
#  如果online redo是不可用的, 那么需要使用RESETLOGS 创建新控制文件打开数据库,
#  联机日志被重置，数据有可能丢失
--
--     Set #1. NORESETLOGS case
--
-- The following commands will create a new control file and use it
-- to open the database.
-- Data used by Recovery Manager will be lost.
-- Additional logs may be required for media recovery of offline
-- Use this only if the current versions of all online logs are
-- available.
-- After mounting the created controlfile, the following SQL
-- statement will place the database in the appropriate
-- protection mode:
--  ALTER DATABASE SET STANDBY DATABASE TO MAXIMIZE PERFORMANCE
#   下面的命令用来创建一个新的控制文件来开启数据库。 用于RMAN的数据将会丢失。
#   对于offline datafiles 可能需要额外的归档日志用来做介质恢复，
#   当当前版本的所有online redo log都没有问题的情况下使用noresetlogs。
STARTUP NOMOUNT
CREATE CONTROLFILE REUSE DATABASE "XIENFEI" NORESETLOGS FORCE LOGGING ARCHIVELOG
    MAXLOGFILES 16
    MAXLOGMEMBERS 3
    MAXDATAFILES 100
    MAXINSTANCES 8
    MAXLOGHISTORY 2921
LOGFILE
  GROUP 1 '/u01/oradata/xienfei/redo01.log'  SIZE 5M,
  GROUP 2 '/u01/oradata/xienfei/redo02.log'  SIZE 5M,
  GROUP 3 '/u01/oradata/xienfei/redo03.log'  SIZE 5M
-- STANDBY LOGFILE
DATAFILE
  '/u01/oradata/xienfei/system01.dbf',
  '/u01/oradata/xienfei/undotbs01.dbf',
  '/u01/oradata/xienfei/sysaux01.dbf',
  '/u01/oradata/xienfei/users01.dbf',
  '/u01/oradata/xienfei/example01.dbf',
  '/u01/oradata/xienfei/xff01.dbf',
  '/u01/oradata/xienfei/cf01.dbf',
  '/u01/oradata/xienfei/cfxff01.dbf'
CHARACTER SET ZHS16GBK
;
-- Commands to re-create incarnation table
-- Below log names MUST be changed to existing filenames on
-- disk. Any one log file from each branch can be used to
-- re-create incarnation records.
-- ALTER DATABASE REGISTER LOGFILE '/u01/archive/1_1_756837539.arc';
#  有些时候可能需要先注册归档日志，再才能够恢复
-- Recovery is required if any of the datafiles are restored backups,
-- or if the last shutdown was not normal or immediate.
#  恢复数据库
RECOVER DATABASE
-- All logs need archiving and a log switch is needed.
#  归档所有日志
ALTER SYSTEM ARCHIVE LOG ALL;
-- Database can now be opened normally.
#  打开数据库
ALTER DATABASE OPEN;
-- Commands to add tempfiles to temporary tablespaces.
-- Online tempfiles have complete space information.
-- Other tempfiles may require adjustment.
#  添加临时表空间
ALTER TABLESPACE TEMP ADD TEMPFILE '/u01/oradata/xienfei/temp01.dbf'
     SIZE 32505856  REUSE AUTOEXTEND ON NEXT 655360  MAXSIZE 32767M;
-- End of tempfile additions.
##    下面的RESETLOGS 重建语句， online redo log 中的内容都会丢失，所有的备份将无效
##    仅仅在online log 损坏的情况下使用 resetlogs 创建控制文件开启数据库。
##    resetlog创建控制文件后的开启步骤与noresetlog有一些不一样，请注意下面步骤
--     Set #2. RESETLOGS case
--
-- The following commands will create a new control file and use it
-- to open the database.
-- Data used by Recovery Manager will be lost.
-- The contents of online logs will be lost and all backups will
-- be invalidated. Use this only if online logs are damaged.
-- After mounting the created controlfile, the following SQL
-- statement will place the database in the appropriate
-- protection mode:
--  ALTER DATABASE SET STANDBY DATABASE TO MAXIMIZE PERFORMANCE
STARTUP NOMOUNT
CREATE CONTROLFILE REUSE DATABASE "XIENFEI" RESETLOGS FORCE LOGGING ARCHIVELOG
    MAXLOGFILES 16
    MAXLOGMEMBERS 3
    MAXDATAFILES 100
    MAXINSTANCES 8
    MAXLOGHISTORY 2921
LOGFILE
  GROUP 1 '/u01/oradata/xienfei/redo01.log'  SIZE 5M,
  GROUP 2 '/u01/oradata/xienfei/redo02.log'  SIZE 5M,
  GROUP 3 '/u01/oradata/xienfei/redo03.log'  SIZE 5M
-- STANDBY LOGFILE
DATAFILE
  '/u01/oradata/xienfei/system01.dbf',
  '/u01/oradata/xienfei/undotbs01.dbf',
  '/u01/oradata/xienfei/sysaux01.dbf',
  '/u01/oradata/xienfei/users01.dbf',
  '/u01/oradata/xienfei/example01.dbf',
  '/u01/oradata/xienfei/xff01.dbf',
  '/u01/oradata/xienfei/cf01.dbf',
  '/u01/oradata/xienfei/cfxff01.dbf'
CHARACTER SET ZHS16GBK
;
-- Commands to re-create incarnation table
-- Below log names MUST be changed to existing filenames on
-- disk. Any one log file from each branch can be used to
-- re-create incarnation records.
#  注册归档日志
-- ALTER DATABASE REGISTER LOGFILE '/u01/archive/1_1_756837539.arc';
-- Recovery is required if any of the datafiles are restored backups,
-- or if the last shutdown was not normal or immediate.
#  使用历史控制文件恢复数据库（因为redo log是新建，所以对于redo 而言，控制文件是新建的）
RECOVER DATABASE USING BACKUP CONTROLFILE
-- Database can now be opened zeroing the online logs.
#  使用RESETLOGS方式打开数据库
ALTER DATABASE OPEN RESETLOGS;
-- Commands to add tempfiles to temporary tablespaces.
-- Online tempfiles have complete space information.
-- Other tempfiles may require adjustment.
#  添加临时表空间
ALTER TABLESPACE TEMP ADD TEMPFILE '/u01/oradata/xienfei/temp01.dbf'
     SIZE 32505856  REUSE AUTOEXTEND ON NEXT 655360  MAXSIZE 32767M;
-- End of tempfile additions.

一、oracle falshback drop
利用flashback drop oracle10g可以对DDL操作进行恢复,oracla提供类似回收站的recyclebin来收集被删除的对象，其实对象在删除的时候oracle把对象写到一个数据字典表中，当用户不需要该对象的时候，可以利用purge命令来从回收站进行清除
select object_name,droptime,dropscn,purge_object,ORIGINAL_NAME from recyclebin;
flashback table f_drop to before drop;
清空回收站：
1）清空一张表：purge table “BIN$N+i42FTvSSemvMrH6frCQg==$0″/table_name;
2）清空一个index：purge index index_name;
2）清空所有对象：PURGE recyclebin;
二、oracle falshback table
对于误drop的table此可以使用本操作，还原drop的table
select t_odu.*,ora_rowscn from a;–查询每条记录对应scn
select dbms_flashback.get_system_change_number from dual;–系统当前scn
alter table t_odu enable row movement;–table row movement
flashback table t_odu to scn 1831189;–基于scn恢复
flashback table t_odu to timestamp to_timestamp(‘2011-6-27 11:45:20′,’yyyy-mm-dd hh24:mi:ss’);–基于时间点
scn补充：
可以通过select ora_rowscn from table 得到每一条结果集当前的SCN，timestamp_to_scn()将scn转换到stmestamp；scn_to_timestamp()将timestamp转换到scn。
三、oracle falshback version query
racle10g falshback 能将所有做了提交的行进行记录，就类似于审计的功能，通过falshback可以查询什么时候执行了什么操作，非常方便，包括闪回版本的查询和审计等
select COUNT(*) from t_query as of scn 1831544;
SELECT COUNT(*) FROM t_query as of timestamp to_timestamp(‘2011-07-21 14:58:00′,’yyyy-mm-dd hh24:mi:ss’);
四、oracle falshback transaction query
回闪事务功能提供对过去某段时间内所完成的事务的查询和撤销
SELECT * FROM flashback_transaction_query a WHERE a.table_name=’T_QUERY’;
补充：
UNDO_SQL 就是当时对表T_QUERY的逆向操作语句

%c 备份片的拷贝数
%d 数据库名称
%D 位于该月中的第几天 (DD)
%M 位于该年中的第几月 (MM)
%F 一个基于DBID唯一的名称,这个格式的形式为c-IIIIIIIIII-YYYYMMDD-QQ,其中IIIIIIIIII为该数据库的DBID，YYYYMMDD为日期，QQ是一个1-256的序列
%n 数据库名称，向右填补到最大八个字符
%u 一个八个字符的名称代表备份集与创建时间
%p 该备份集中的备份片号，从1开始到创建的文件数
%U 一个唯一的文件名，代表%u_%p_%c
%s 备份集的号
%t 备份集时间戳
%T 年月日格式(YYYYMMDD)

startup nomount;
create pfile=’/tmp/pfile’ from spfile;
修改pfile
*._allow_resetlogs_corruption=true
*._corrupted_rollback_segments=(_SYSSMU1$,_SYSSMU2$,_SYSSMU3$,_SYSSMU4$,
_SYSSMU5$,_SYSSMU6$,_SYSSMU7$,_SYSSMU8$,_SYSSMU9$,_SYSSMU10$)
startup pfile=’/tmp/pfile’ mount;
–undo数据文件不用离线也可以打开的时候（2），不行采用下面的方法
alter database datafile 2 offline drop;
alter database open;
CREATE UNDO TABLESPACE UNDOTBS01
DATAFILE ‘/opt/oracle/oradata/xifenfei/UNDOTBS01.dbf’ SIZE 50M;
select segment_name,status from dba_rollback_segs;–查看是否有回滚段被创建，处于offline状态
shutdown immediate;
修改pfile：
*.undo_tablespace=’UNDOTBS01′
startup pfile=’/tmp/pfile’
–alter tablespace undotbs1 offline normal;（2）–使数据文件先离线，如果开始已经离线，这里不需要处理
select segment_name,status from dba_rollback_segs;
drop rollback segment “_SYSSMUx$”;
drop tablespace UNDOTBS02 including contents and datafiles;
select * from v$recover_file;–验证是否还有文件需要恢复
shutdown immediate
修改参数文件
#*._allow_resetlogs_corruption=true
#*._corrupted_rollback_segments=(_SYSSMU1$,_SYSSMU2$,_SYSSMU3$,_SYSSMU4$,_SYSSMU5$,
_SYSSMU6$,_SYSSMU7$,_SYSSMU8$,_SYSSMU9$,_SYSSMU10$)
startup pfile=’/tmp/pfile’;
create spfile from pfile=’/tmp/pfile’;

startup nomount;
create pfile=’/tmp/pfile’ from spfile;
修改pfile
*.undo_management=’MANUAL’
*.undo_tablespace=’SYSTEM’
#*.undo_tablespace=’UNDOTBS02′
#*.undo_management=’AUTO’
startup pfile=’/tmp/pfile’ mount;
alter database datafile 2 offline drop;
alter database open;
drop tablespace undotbs1 including contents;
select segment_name,status from dba_rollback_segs;
drop rollback segment “_SYSSMUx”$;
drop tablespace undotbs1 including contents;
CREATE UNDO TABLESPACE UNDOTBS02
DATAFILE ‘/opt/oracle/oradata/xifenfei/UNDOTBS02.dbf’ SIZE 50M
shutdown immediate;
修改pfile
#*.undo_management=’MANUAL’
#*.undo_tablespace=’SYSTEM’
*.undo_tablespace=’UNDOTBS02′
*.undo_management=’AUTO’
startup pfile=’/tmp/pfile’;
create spfile from pfile=’/tmp/pfile’;