一前言

每个 DM 数据库都有一个名为 dm.ctl 的控制文件。控制文件是一个二进制文件，它记录了数据库必要的初始信息，如果控制文件损坏，数据库则无法正常启动。

二控制文件内容

控制文件位置是在配置文件dm.ini中指定的：
[dmdba@dm3 IESDB]$ cat dm.ini |grep CTL
CTL_PATH = /usr/appsoft/dmdbms/data/IESDB/dm.ctl #ctl file path
CTL_BAK_PATH = /usr/appsoft/dmdbms/data/IESDB/ctl_bak #dm.ctl backup path
CTL_BAK_NUM = 10 #backup number of dm.ctl, allowed to keep one more backup file besides $pecified number.
RAC_N_CTLS = 10000 #Number Of LBS/GBS ctls
控制文件主要包含以下内容：

数据库名称；
数据库服务器模式；
OGUID 唯一标识；
数据库服务器版本；
数据文件版本；
数据库的启动次数；
数据库最近一次启动时间；
表空间信息，包括表空间名，表空间物理文件路径等，记录了所有数据库中使用的表空间，数组的方式保存起来；

控制文件校验码，校验码由数据库服务器在每次修改控制文件后计算生成，保证控制文件合法性，防止文件损坏及手工修改。

三、控制文件转换

控制文件本身是二进制文件，无法正常查看其具体内容，达梦提供了转换工具dmctlcvt可以将其转换为文本文件，这样就可以方便修改和查看。
Dmctlcvt工具语法：
[dmdba@dm3 IESDB]$ dmctlcvt -h
DMCTLCVT V7.6.0.171-Build(2019.07.02-109059)ENT

Format: ./dmctlcvt KEYWORD=value
Note: ctl file name must be dm.ctl or dmmpp.ctl or dmwatcher.ctl

Keyword Explanation

TYPE 1 convert ctl file(dm.ctl or dmmpp.ctl) to txt file
2 convert txt file to ctl file(dm.ctl or dmmpp.ctl)
3 convert txt file to ctl file(dmwatcher.ctl), the dest_file_path not include file name
4 convert ctl file(dmwatcher.ctl) to txt file
SRC Source file
DEST Destination file
DCR_INI the path of dmdcr.ini
HELP Show this help info

Example:
./dmctlcvt TYPE=1 SRC=/opt/dmdbms/data/dameng/dm.ctl DEST=/opt/dmdbms/data/dameng/dmctl.txt
./dmctlcvt TYPE=2 SRC=/opt/dmdbms/data/dameng/dmctl.txt DEST=/opt/dmdbms/data/dameng/dm.ctl
./dmctlcvt TYPE=3 SRC=/opt/dmdbms/data/dameng/dmwatcher.txt DEST=/opt/dmdbms/data/dameng
./dmctlcvt TYPE=4 SRC=/opt/dmdbms/data/dameng/dmwatcher.ctl DEST=/opt/dmdbms/data/dameng/dmwatcher_ctl.txt
从语法中可以看到，TYPE为1或2时，支持控制文件与文本文件的相互转换。
下面我们将控制文件转换为文本文件，并查看一下其具体内容：
1.转换文本文件
[dmdba@dm3 IESDB]$ dmctlcvt TYPE=1 src=/usr/appsoft/dmdbms/data/IESDB/dm.ctl dest=/tmp/dmctl.txt
DMCTLCVT V7.6.0.171-Build(2019.07.02-109059)ENT
convert ctl to txt succes$!
2.查看文件内容
[dmdba@dm3 IESDB]$ cat /tmp/dmctl.txt
##############################################################################

please do not adjust parameter order, ensure the ctl have no difference

##########################################################################

database name

dbname=IESDB

server mode

svr_mode=0
#OGUID
oguid=0

db server version

version=117507755

database version

db_version=458762

pseg version

pseg_version=458762
#SGUID
sguid=-1677197550
#NEXT_TS_ID
next_ts_id=6
#RAC_NODES
rac_nodes=0
#NEXT_HTS_ID
next_htsid=1
#TIME_FLAG
time_flag=170
#STARTUP_CNT
startup_cnt=1
#LAST_STARTUP_TIME
last_startup_time=2020-5-26 15:21:53
#DM7_DCT_VERSION
dm7_dct_version=2
#DM8_DCT_VERSION
dm8_dct_version=0
#===============================================
#===============================================

table space name

ts_name=SYSTEM

table space ID

ts_id=0

table space status

t$_state=0

table space cache

ts_cache=

RAC node number

ts_nth=0

table space create time

ts_create_time=2019-9-21 22:37:7

table space modify time

ts_modify_time=2019-9-21 22:37:7

table space encrypt flag

ts_encrypt_flag=0
#-----------------------------------------------

file path

fil_path=/usr/appsoft/dmdbms/data/IESDB/SYSTEM.DBF

mirror path

mirror_path=

file id

fil_id=0

whether the file is auto extend

autoextend=1

file create time

fil_create_time=2019-9-21 22:37:7

file modify time

fil_modify_time=2019-9-21 22:37:7

the max size of file

fil_max_size=0

next size of file

fil_next_size=0
#===============================================

table space name

ts_name=ROLL

table space ID

ts_id=1

table space status

t$_state=0

table space cache

ts_cache=

RAC node number

ts_nth=0

table space create time

ts_create_time=2019-9-21 22:37:7

table space modify time

ts_modify_time=2019-9-21 22:37:7

table space encrypt flag

ts_encrypt_flag=0
#-----------------------------------------------

file path

fil_path=/usr/appsoft/dmdbms/data/IESDB/ROLL.DBF

mirror path

mirror_path=

file id

fil_id=0

whether the file is auto extend

autoextend=1

file create time

fil_create_time=2019-9-21 22:37:7

file modify time

fil_modify_time=2019-9-21 22:37:7

the max size of file

fil_max_size=0

next size of file

fil_next_size=0
#===============================================

table space name

ts_name=RLOG

table space ID

ts_id=2

table space status

t$_state=0

table space cache

ts_cache=

RAC node number

ts_nth=0

table space create time

ts_create_time=2019-9-21 22:37:7

table space modify time

ts_modify_time=2019-9-21 22:37:7

table space encrypt flag

ts_encrypt_flag=0
#-----------------------------------------------

file path

fil_path=/usr/appsoft/dmdbms/data/IESDB/IESDB01.log

mirror path

mirror_path=

file id

fil_id=0

whether the file is auto extend

autoextend=1

file create time

fil_create_time=2019-9-21 22:37:7

file modify time

fil_modify_time=2019-9-21 22:37:7

the max size of file

fil_max_size=0

next size of file

fil_next_size=0

file path

fil_path=/usr/appsoft/dmdbms/data/IESDB/IESDB02.log

mirror path

mirror_path=

file id

fil_id=1

whether the file is auto extend

autoextend=1

file create time

fil_create_time=2019-9-21 22:37:7

file modify time

fil_modify_time=2019-9-21 22:37:7

the max size of file

fil_max_size=0

next size of file

fil_next_size=0
#===============================================

table space name

ts_name=MAIN

table space ID

ts_id=4

table space status

t$_state=0

table space cache

ts_cache=

RAC node number

ts_nth=0

table space create time

ts_create_time=2019-9-21 22:37:8

table space modify time

ts_modify_time=2019-9-21 22:37:8

table space encrypt flag

ts_encrypt_flag=0
#-----------------------------------------------

file path

fil_path=/usr/appsoft/dmdbms/data/IESDB/MAIN.DBF

mirror path

mirror_path=

file id

fil_id=0

whether the file is auto extend

autoextend=1

file create time

fil_create_time=2019-9-21 22:37:8

file modify time

fil_modify_time=2019-9-21 22:37:8

the max size of file

fil_max_size=0

next size of file

fil_next_size=0
#===============================================

table space name

ts_name=SEMITER

table space ID

ts_id=5

table space status

t$_state=0

table space cache

ts_cache=NORMAL

RAC node number

ts_nth=0

table space create time

ts_create_time=2020-5-26 14:58:40

table space modify time

ts_modify_time=2020-5-26 14:58:49

table space encrypt flag

ts_encrypt_flag=0
#-----------------------------------------------

file path

fil_path=/usr/appsoft/dmdbms/data/IESDB/semiter01.dbf

mirror path

mirror_path=

file id

fil_id=0

whether the file is auto extend

autoextend=1

file create time

fil_create_time=2020-5-26 14:58:40

file modify time

fil_modify_time=2020-5-26 14:58:40

the max size of file

fil_max_size=0

next size of file

fil_next_size=0

file path

fil_path=/usr/appsoft/dmdbms/data/semiter02.dbf

mirror path

mirror_path=

file id

fil_id=1

whether the file is auto extend

autoextend=1

file create time

fil_create_time=2020-5-26 14:58:49

file modify time

fil_modify_time=2020-5-26 14:58:49

the max size of file

fil_max_size=0

next size of file

fil_next_size=0
#===============================================

HUGE table space name

htsname=HMAIN

HUGE table space id

htsid=0
#HUGE table space share flag
htsflag=0

HUGE table space create time

hts_create_time=2019-9-21 22:37:8

HUGE table space modify time

hts_modify_time=2019-9-21 22:37:8

HUGE table space path

htspath=/usr/appsoft/dmdbms/data/IESDB/HMAIN
#===============================================

四重建控制文件

我们可以根据控制文件的内容进行修改，并重建控制文件以完成实际修改。在数据库关闭状态下，我们可以将数据文件移动到其它位置，再修改控制文件中数据文件的路径，然后重建控制文件，来完成数据文件路径的更换。
其实，基本上涉及到路径修改的，都可以通过重建控制文件的方式来完成。
在oracle数据库中，即使控制文件损坏了，可以通过重建的方式来进行恢复，但达梦数据库如果控制文件损坏了，经过实验无法通过这种方式进行恢复；只能通过重建实例，必须相同环境的实例，包括数据库版本、操作系统版本、各种文件路径等。

4.1 创建测试环境

创建如下表空间及用户用于数据文件迁移测试。表空间： create tablespace "SEMITER" datafile '/usr/appsoft/dmdbms/data/TEST/semiter01.dbf' size 128 CACHE = NORMAL; 表空间扩展： alter tablespace "SEMITER" add datafile '/usr/appsoft/dmdbms/data/TEST/semiter02.dbf' size 128; 用户： create user "SEMITER" identified by "semiter123" default tablespace "SEMITER"; 角色与权限： grant "DBA","PUBLIC","RESOURCE" to "SEMITER"; alter user "SEMITER" limit failed_login_attemps unlimited, pas$word_lock_time unlimited, pas$word_grace_time unlimited; 表空间SEMITER中有两个数据文件，semiter01.dbf和semiter02.dbf，我们将迁移semiter02.dbf到新的目录/usr/appsoft/dmdbms/data下。迁移前数据文件路径如下： SQL> select t.name tablespace_name,t.id file_id,d.path file_name,d.total_size*SF_GET_PAGE_SIZE()/1024/1024		'M' total_space from v$tablespace t, v$datafile d where t.id=d.group_id and t.name='SEMITER'; 行号 tablespace_name file_id file_name total_space

1 SEMITER 5 /usr/appsoft/dmdbms/data/TEST/semiter02.dbf 128M
2 SEMITER 5 /usr/appsoft/dmdbms/data/TEST/semiter01.dbf 128M
已用时间: 2.918(毫秒). 执行号:19.

4.2 关闭实例并转换控制文件为文本文件

1.关闭数据库实例：
[root@dm3 data]# /etc/init.d/DmServiceTEST stop
Stopping DmServiceTEST: [ OK ]
2.转换控制文件
[dmdba@dm3 usr]$ dmctlcvt type=1 src=/usr/appsoft/dmdbms/data/TEST/dm.ctl dest=/tmp/semiter.txt
DMCTLCVT V7.6.0.171-Build(2019.07.02-109059)ENT
convert ctl to txt succes$!

4.3 拷贝数据文件到新的路径

[dmdba@dm3 TEST]$ pwd
/usr/appsoft/dmdbms/data/TEST
[dmdba@dm3 TEST]$ mv semiter02.dbf ../

4.4 修改文本文件中数据文件路径到新路径并重建控制文件

[dmdba@dm3 IESDB]$ cat /tmp/semiter.txt |grep semiter02.dbf
fil_path=/usr/appsoft/dmdbms/data/semiter02.dbf

[dmdba@dm3 IESDB]$ dmctlcvt type=2 src=/tmp/semiter.txt dest=/usr/appsoft/dmdbms/data/IESDB/dm.ctl
DMCTLCVT V7.6.0.171-Build(2019.07.02-109059)ENT
convert txt to ctl succe$s!
[dmdba@dm3 IESDB]$

4.5 启动数据库并进行验证

[dmdba@dm3 IESDB]$ /etc/init.d/DmServiceIESDB start
Starting DmServiceIESDB: [ OK ]

SQL> select t.name tablespace_name,t.id file_id,d.path file_name,d.total_size*SF_GET_PAGE_SIZE()/1024/1024||'M' total_space from v$tablespace t, v$datafile d where t.id=d.group_id and t.name='SEMITER';

行号 tablespace_name file_id file_name total_space

1 SEMITER 5 /usr/appsoft/dmdbms/data/semiter02.dbf 128M
2 SEMITER 5 /usr/appsoft/dmdbms/data/IESDB/semiter01.dbf 128M
已用时间: 9.828(毫秒). 执行号:4.
从上面的输出中可以明显看到，semiter02.dbf的路径已经更改，至此我们就完成了达梦数据库下数据文件路径的修改。

Linux平台达梦数据库V7之控制文件管理

一 前言

二 控制文件内容

三、控制文件转换

Keyword Explanation

please do not adjust parameter order, ensure the ctl have no difference

database name

server mode

db server version

database version

pseg version

table space name

table space ID

table space status

table space cache

RAC node number

table space create time

table space modify time

table space encrypt flag

file path

mirror path

file id

whether the file is auto extend

file create time

file modify time

the max size of file

next size of file

table space name

table space ID

table space status

table space cache

RAC node number

table space create time

table space modify time

table space encrypt flag

file path

mirror path

file id

whether the file is auto extend

file create time

file modify time

the max size of file

next size of file

table space name

table space ID

table space status

table space cache

RAC node number

table space create time

table space modify time

table space encrypt flag

file path

mirror path

file id

whether the file is auto extend

file create time

file modify time

the max size of file

next size of file

file path

mirror path

file id

whether the file is auto extend

file create time

file modify time

the max size of file

next size of file

table space name

table space ID

table space status

table space cache

RAC node number

table space create time

table space modify time

table space encrypt flag

file path

mirror path

file id

whether the file is auto extend

file create time

一前言

二控制文件内容

四重建控制文件