oracle 中的控制文件和数据文件

1、数据文件：

Oracle数据库中每个表空间（tablespace）都是由一个或多个物理数据文件（datafile）构成的。

当一个数据文件（datafile）首次被创建时，为其分配的磁盘空间被格式化为Oracle格式，此时其中尚不包含任何用户数据。Oracle将使用这些空间存储属于（

与此数据文件对应的）表空间的段（segment），这些空间专为Oracle使用。随着表空间内的数据增长，Oracle使用数据文件中的可用空间为段分配新的数据扩展（extent）。御敏启

2、控制文件

控制文件（control

file）是一个二进制文件，供数据库启动及正常工作时使用。

在数据库运行过程中，控制文件会频繁地被Oracle修改，因此数据库处于开启（open）状态时控制文件必须可写。如果控制文件因故不能访问，数据库

也将无法正常镇如工作。

每当添加，重命名，或移除拿升数据库中的数据文件（datafile）及重做日志文件（redo

log

file）时，控制文件（control

file）就会被更新以反映这些数据库物理结构变化。

环境:

OS:Red Hat Linux As 5

DB:10.2.0.4

在全部控制差咐悔文件丢失或损坏，而且没虚正有备份的情况下,可以使用重建控制文件的办法打开数据库.以下模拟所有的控制文件丢失的情况下重建控制文件.

1.备份控制文件(数据库mount或是open状态)

SQL>select status from v$instance

STATUS

------------

OPEN

SQL>alter database backup controlfile to trace as '/u01/ftp/bak_controlfile'

2.删除控制文件

[oracle@hxl oracl]$ rm control01.ctl

rm: remove regular file `control01.ctl'? y

[oracle@hxl oracl]$ rm control02.ctl

rm: remove regular file `control02.ctl'? y

[oracle@hxl oracl]$ rm control03.ctl

rm: remove regular file `control03.ctl'? y

3.关闭数据库后尝试打开数据库

SQL>shutdown immediate

Database closed.

Database dismounted.

ORACLE instance shut down.

SQL>startup

ORACLE instance started.

Total System Global Area 734003200 bytes

Fixed Size 1221564 bytes

Variable Size 218106948 bytes

Database Buffers 511705088 bytes

Redo Buffers2969600 bytes

ORA-00205: error in identifying control file, check alert log for more info

这个时候数据无法打开,以为我们已经删除了控制文件.

4.查看备份控制文件的内容

[oracle@hxl ftp]$ more bak_controlfile

-- The following are current System-scope REDO Log Archival related

-- parameters and can be included in the database initialization file.

--

-- LOG_ARCHIVE_DEST=''

-- LOG_ARCHIVE_DUPLEX_DEST=''

--

-- LOG_ARCHIVE_FORMAT=%t_%s_%r.dbf

--

-- DB_UNIQUE_NAME="oracl"

--

-- LOG_ARCHIVE_CONFIG='SEND, RECEIVE, NODG_CONFIG'

-- LOG_ARCHIVE_MAX_PROCESSES=2

-- STANDBY_FILE_MANAGEMENT=MANUAL

-- STANDBY_ARCHIVE_DEST=?/dbs/arch

-- FAL_CLIENT=''

-- FAL_SERVER='简渣'

--

-- LOG_ARCHIVE_DEST_10='LOCATION=USE_DB_RECOVERY_FILE_DEST'

-- LOG_ARCHIVE_DEST_10='OPTIONAL REOPEN=300 NODELAY'

-- LOG_ARCHIVE_DEST_10='ARCH NOAFFIRM NOEXPEDITE NOVERIFY SYNC'

-- LOG_ARCHIVE_DEST_10='REGISTER NOALTERNATE NODEPENDENCY'

-- LOG_ARCHIVE_DEST_10='NOMAX_FAILURE NOQUOTA_SIZE NOQUOTA_USED NODB_UNIQUE_NAME'

-- LOG_ARCHIVE_DEST_10='VALID_FOR=(PRIMARY_ROLE,ONLINE_LOGFILES)'

-- LOG_ARCHIVE_DEST_STATE_10=ENABLE

--

-- 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.

--

-- 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

STARTUP NOMOUNT

CREATE CONTROLFILE REUSE DATABASE "ORACL" NORESETLOGS ARCHIVELOG

MAXLOGFILES 16

MAXLOGMEMBERS 3

MAXDATAFILES 100

MAXINSTANCES 8

MAXLOGHISTORY 292

LOGFILE

GROUP 1 '/u01/app/oracle/oradata/oracl/redo01.log' SIZE 50M,

GROUP 2 '/u01/app/oracle/oradata/oracl/redo02.log' SIZE 50M,

GROUP 3 '/u01/app/oracle/oradata/oracl/redo03.log' SIZE 50M

-- STANDBY LOGFILE

DATAFILE

'/u01/app/oracle/oradata/oracl/system01.dbf',

'/u01/app/oracle/oradata/oracl/undotbs01.dbf',

'/u01/app/oracle/oradata/oracl/sysaux01.dbf',

'/u01/app/oracle/oradata/oracl/users01.dbf'

CHARACTER SET WE8ISO8859P1

-- 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/app/oracle/flash_recovery_area/ORACL/archivelog/2012_06_12/o1_mf_1_1_%u_.arc'

-- ALTER DATABASE REGISTER LOGFILE '/u01/app/oracle/flash_recovery_area/ORACL/archivelog/2012_06_12/o1_mf_1_1_%u_.arc'

-- ALTER DATABASE REGISTER LOGFILE '/u01/app/oracle/flash_recovery_area/ORACL/archivelog/2012_06_12/o1_mf_1_1_%u_.arc'

-- ALTER DATABASE REGISTER LOGFILE '/u01/app/oracle/flash_recovery_area/ORACL/archivelog/2012_06_12/o1_mf_1_1_%u_.arc'

-- Recovery is required if any of the datafiles are restored backups,

-- or if the last shutdown was not normal or immediate.

RECOVER DATABASE

-- All logs need archiving and a log switch is needed.

ALTER SYSTEM ARCHIVE LOG ALL

-- Database can now be opened normally.

ALTER DATABASE OPEN

-- Commands to add tempfiles to temporary tablespaces.

-- Online tempfiles have complete space information.

-- Other tempfiles may require adjustment.

ALTER TABLESPACE TEMP ADD TEMPFILE '/u01/app/oracle/oradata/oracl/temp01.dbf'

SIZE 20971520 REUSE AUTOEXTEND ON NEXT 655360 MAXSIZE 32767M

-- End of tempfile additions.

--

-- 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 "ORACL" RESETLOGS ARCHIVELOG

MAXLOGFILES 16

MAXLOGMEMBERS 3

MAXDATAFILES 100

MAXINSTANCES 8

MAXLOGHISTORY 292

LOGFILE

GROUP 1 '/u01/app/oracle/oradata/oracl/redo01.log' SIZE 50M,

GROUP 2 '/u01/app/oracle/oradata/oracl/redo02.log' SIZE 50M,

GROUP 3 '/u01/app/oracle/oradata/oracl/redo03.log' SIZE 50M

-- STANDBY LOGFILE

DATAFILE

'/u01/app/oracle/oradata/oracl/system01.dbf',

'/u01/app/oracle/oradata/oracl/undotbs01.dbf',

'/u01/app/oracle/oradata/oracl/sysaux01.dbf',

'/u01/app/oracle/oradata/oracl/users01.dbf'

CHARACTER SET WE8ISO8859P1

-- 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/app/oracle/flash_recovery_area/ORACL/archivelog/2012_06_12/o1_mf_1_1_%u_.arc'

-- ALTER DATABASE REGISTER LOGFILE '/u01/app/oracle/flash_recovery_area/ORACL/archivelog/2012_06_12/o1_mf_1_1_%u_.arc'

-- ALTER DATABASE REGISTER LOGFILE '/u01/app/oracle/flash_recovery_area/ORACL/archivelog/2012_06_12/o1_mf_1_1_%u_.arc'

-- ALTER DATABASE REGISTER LOGFILE '/u01/app/oracle/flash_recovery_area/ORACL/archivelog/2012_06_12/o1_mf_1_1_%u_.arc'

-- Recovery is required if any of the datafiles are restored backups,

-- or if the last shutdown was not normal or immediate.

RECOVER DATABASE USING BACKUP CONTROLFILE

-- Database can now be opened zeroing the online logs.

ALTER DATABASE OPEN RESETLOGS

-- Commands to add tempfiles to temporary tablespaces.

-- Online tempfiles have complete space information.

-- Other tempfiles may require adjustment.

ALTER TABLESPACE TEMP ADD TEMPFILE '/u01/app/oracle/oradata/oracl/temp01.dbf'

SIZE 20971520 REUSE AUTOEXTEND ON NEXT 655360 MAXSIZE 32767M

-- End of tempfile additions.

--

5.从备份控制文件中提取我们需要的部分,这里我们选择RESETLOGS,将如下内容保存文件为

create_confile.sql

CREATE CONTROLFILE REUSE DATABASE "ORACL" RESETLOGS ARCHIVELOG

MAXLOGFILES 16

MAXLOGMEMBERS 3

MAXDATAFILES 100

MAXINSTANCES 8

MAXLOGHISTORY 292

LOGFILE

GROUP 1 '/u01/app/oracle/oradata/oracl/redo01.log' SIZE 50M,

GROUP 2 '/u01/app/oracle/oradata/oracl/redo02.log' SIZE 50M,

GROUP 3 '/u01/app/oracle/oradata/oracl/redo03.log' SIZE 50M

-- STANDBY LOGFILE

DATAFILE

'/u01/app/oracle/oradata/oracl/system01.dbf',

'/u01/app/oracle/oradata/oracl/undotbs01.dbf',

'/u01/app/oracle/oradata/oracl/sysaux01.dbf',

'/u01/app/oracle/oradata/oracl/users01.dbf'

CHARACTER SET WE8ISO8859P1

6.执行create_confile.sql

SQL>set sqlblanklines on -- 因为文件中有空行,需要将该选项打开,否则执行的时候报语法错误

SQL>@/u01/ftp/create_confile.sql

SQL>alter database open resetlogs

Database altered.

说明:

重建控制文件后,若备份信息是存储在控制文件的,该信息会丢失.

创建控制文件需模顷要在nomount状态下，你液携这闹码伏个错误说明你在mount下，shutdown immediate关闭数据库，然后startup nomount，再重建控制文件。

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