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OracleEXP和IMP用法和介绍

正在看的ORACLE教程是:OracleEXP和IMP用法和介绍。

1、Export/Import的用处
Oracle Export/Import工具用于在数据库之间传递数据。
Export从数据库中导出数据到dump文件中
Import从dump文件中到入数据导数据库中
下面是一般使用他们的情况
(1)、两个数据库之间传送数据
同一个版本的oracle Server之间
不同版本的oracle Server之间
同种OS之间
不同种OS之间
(2)、用于数据库的备份和恢复
(3)、从一个SCHEMA传送到另一个SCHEMA
(4)、从一个TABLESPACE传送到另一个TABLESPACE

2、DUMP文件
EXPORT到出的是二进制格式的文件,不可以手工编辑,否则会损坏数据。
该文件在ORACLE支持的任何平台上都是一样的格式,可以在各平台上通用。

DUMP文件在IMPORT时采用向上兼容方式,就是说ORALCE7的DUMP文件可以导入
到ORACLE8中,但是版本相差很大的版本之间可能有问题。

3、EXPORT/IMPORT过程
EXPORT导出的DUMP文件包含两种基本类型的数据
- DDL (Data Dictionary Language)
- Data
DUMP文件包含所有重新创建Data Dictionary的DDL语句,基本上是可以读的格式

但是应该注意的是,千万不要用文本编辑器编辑之,oracle说不支持这样做的。

下面列出的是DUMP文件中包括的ORACLE对象,分为TABLE/USER/FULL方式,有些对

只是在FULL方式下才有(比如public synonyms, users, roles, rollback segm
ents等)

Table mode User Mode Full Database Mode
---------------------- ---------------------- ----------------------
---
Table definitions Table definitions Table definitions
Table data Table data Table data
Owner's table grants Owner's grants Grants
Owner's table indexes Owner's indexes Indexes
Table constraints Table constraints Table constraints
Table triggers &nbs

[1] ...

正在看的ORACLE教程是:OracleEXP和IMP用法和介绍。p; Table triggers All triggers
Clusters Clusters
Database links Database links
Job queues Job queues
Refresh groups Refresh groups
Sequences Sequences
Snapshots Snapshots
Snapshot logs Snapshot logs
Stored procedures Stored procedures

[2] ...

正在看的ORACLE教程是:OracleEXP和IMP用法和介绍。
Private synonyms All synonyms
Views Views
Profiles
Replication catalog
Resource cost
Roles
Rollback segments
 

[3] ...

正在看的ORACLE教程是:OracleEXP和IMP用法和介绍。; System audit options
System privileges
Tablespace definitions
Tablespace quotas
User definitions

4、IMPORT时的对象倒入顺序
在倒入数据时,ORACLE有一个特定的顺序,可能随数据库版本不同而有所变化,
但是
现在是这样的。

1. Tablespaces 14. Snapshot Logs
2. Profiles 15. Job Queues

[4] ...

正在看的ORACLE教程是:OracleEXP和IMP用法和介绍。 3. Users 16. Refresh Groups
4. Roles 17. Cluster Definitions
5. System Privilege Grants 18. Tables (also grants,commen
ts,
6. Role Grants indexes, constraints, audi
ting)
7. Default Roles 19. Referential Integrity

8. Tablespace Quotas 20. POSTTABLES actions

9. Resource Costs 21. Synonyms
10. Rollback Segments 22. Views
11. Database Links &nbs

[5] ...

正在看的ORACLE教程是:OracleEXP和IMP用法和介绍。p; 23. Stored Procedures
12. Sequences 24. Triggers, Defaults and Aud
iting
13. Snapshots

按这个顺序主要是解决对象之间依赖关系可能产生的问题。TRIGGER最后导入,所
以在INSERT
数据到数据库时不会激发TRIGGER。在导入后可能会有一些状态是INVALID的PROC
EDURE,主要
是IMPORT时会影响一些数据库对象,而IMPORT并不重新编译PROCEDURE,从而造成
这种情况,
可以重新编译之,就能解决这个问题。

5、兼容性问题
IMPORT工具可以处理EXPORT 5.1.22之后的版本导出的DUMP文件,所以你用ORACL
E7的IMPORT
处理ORACLE6的DUMP文件,依次类推,但是ORACLE如果版本相差很大有可能不能处
理。具体的
问题可以参照相应的文档,比如有关参数设置等(COMPATIBLE参数)

6、EXPORT需要的VIEW
EXPORT需要的VIEW是由CATEXP.SQL创建,这些内部VIEW用于EXPORT组织DUMP文件
中数据格式。
大部分VIEW用于收集创建DDL语句的,其他的主要供ORACLE开发人员用。

这些VIEW在不同ORACLE版本之间有可能不同,每个版本可能都有新的特性加入。
所以在新的
版本里面执行旧的dump文件会有错误,一般可以执行CATEXP.SQL解决这些问题,
解决向后兼容
问题的一般步骤如下:

导出数据库的版本比目标数据库老的情况:
- 在需要导入的目标数据库中执行旧的CATEXP.SQL
- 使用旧的EXPORT导出DUMP文件
- 使用旧的IMPORT导入到数据库中
- 在数据库中执行新的CATEXP.SQL,以恢复该版本的EXPORT VIEW

导出数据库的版本比目标数据库新的情况:
- 在需要导入的目标数据库中执行新的CATEXP.SQL
- 使用新的EXPORT导出DUMP文件
- 使用新的IMPORT导入到数据库中
- 在数据库中执行旧的CATEXP.SQL,以恢复该版本的EXPORT VIEW

7、碎片整理
EXPORT/IMPORT一个很重要的应用方面就是整理碎片。因为如果时初次IMPPORT,

就会重新CREATE TABLE 再导入数据,所以整张表都是连续存放的。另外缺省情况

下EXPORT会在生成DUMP文件是“压缩(COMPRESS)”TABLE,但是这种压缩在很多情

[6] ...

正在看的ORACLE教程是:OracleEXP和IMP用法和介绍。下被误解。事实上,COMPRESS是改变STORAGE参数INITIAL的值。比如:

CREATE TABLE .... STORAGE( INITIAL 10K NEXT 10K..)
现在数据已经扩展到100个EXTENT,如果采用COMPRESS=Y来EXPORT数据,
则产生的语句时 STORAGE( INITIAL 1000K NEXT 10K)

我们可以看到NEXT值并没有改变,而INITIAL是所有EXTENT的总和。所以会出现

如下情况,表A有4个100M的EXTENT,执行DELETE FROM A,然后再用COMPRESS=Y 导

出数据,产生的CREATE TABLE语句将有400M的INITIAL EXTENT。即使这是TABLE中

已经没有数据!!这是的DUMP文件即使很小,但是在IMPORT时就会产生一个巨大

TABLE.

另外,也可能会超过DATAFILE的大小。比如,有4个50M的数据文件,其中表A有

15个10M的EXTENT,如果采用COMPRESS=Y的方式导出数据,将会有INITIAL=150M,

那么在重新导入时,不能分配一个150M的EXTENT,因为单个EXTENT不能跨多个文
件。

8、在USER和TABLESPACE之间传送数据
一般情况下EXPORT的数据要恢复到它原来的地方去。如果SCOTT用户的表以TABLE

或USER方式EXPORT数据,在IMPORT时,如果SCOTT用户不存在,则会报错!

以FULL方式导出的数据带有CREATE USER的信息,所以会自己创建USER来存放数据


当然可以在IMPORT时使用FROMUSER和TOUSER参数来确定要导入的USER,但是要保

TOUSER一定已经存在啦。

[NextPage]


9、EXPORT/IMPORT对SQUENCE的影响
在两种情况下,EXPORT/IMPORT会对SEQUENCE。
(1)如果在EXPORT时,用户正在取SEQUENCE的值,可能造成SEQUENCE的不一致。

(2)另外如果SEQUENCE使用CACHE,在EXPORT时,那些在CACHE中的值就会被忽略
的,
只是从数据字典里面取当前值EXPORT。

如果在进行FULL方式的EXPORT/IMPORT时,恰好在用sequence更新表中某列数据,

而且不是上面两种情况,则导出的是更新前的数据。

如果采用常规路径方式,每一行数据都是用INSERT语句,一致性检查和INSERT T
RIGGER
如果采用DIRECT方式,某些约束和trigger可能不触发,如果在trigger中使用
sequence.nextval,将会对sequence有影响。

参数解:

E:\>exp help=y

通过输入 EXP 命令和用户名/口令,您可以
在用户 / 口令之后的命令:

实例: EXP SCOTT/TIGER

或者,您也可以通过输入跟有各种参数的 EXP 命令来控制“导出”的运行方式。
要指定参数,您可以使用关键字:

格式: EXP KEYWORD=value 或 KEYWORD=(value1,value2,...,valueN)
实例: EXP SCOTT/TIGER GRANTS=Y TABLES=(EMP,DEPT,MGR)
或 TABLES=(T1: P1,T1: P2),如果 T1 是分区表

USERID 必须是命令行中的第一个参数。

关键字 说明(默认)
---------------------------------------------------
USERID 用户名/口令
FULL 导出整个文件 (N)
BUFFER 数据

[7] ...

正在看的ORACLE教程是:OracleEXP和IMP用法和介绍。缓冲区的大小
OWNER 所有者用户名列表
FILE 输出文件 (EXPDAT.DMP)
TABLES 表名列表
COMPRESS 导入一个范围 (Y)
RECORDLENGTH IO 记录的长度
GRANTS 导出权限 (Y)
INCTYPE 增量导出类型
INDEXES 导出索引 (Y)
RECORD 跟踪增量导出 (Y)
ROWS 导出数据行 (Y)
PARFILE 参数文件名
CONSTRAINTS 导出限制 (Y)
CONSISTENT 交叉表一致性
LOG 屏幕输出的日志文件
STATISTICS 分析对象 (ESTIMATE)
DIRECT 直接路径 (N)
TRIGGERS 导出触发器 (Y)
FEEDBACK 显示每 x 行 (0) 的进度
FILESIZE 各转储文件的最大尺寸
QUERY 选定导出表子集的子句

下列关键字仅用于可传输的表空间
TRANSPORT_TABLESPACE 导出可传输的表空间元数据 (N)
TABLESPACES 将传输的表空间列表

E:\>imp help=y

可以通过输入 IMP 命令和您的用户名/口令
跟有您的用户名 / 口令的命令:

实例: IMP SCOTT/TIGER

或者, 可以通过输入 IMP 命令和各种自变量来控制“导入”按照不同参数。
要指定参数,您可以使用关键字:

格式: IMP KEYWORD=value 或 KEYWORD=(value1,value2,...,vlaueN)
实例: IMP SCOTT/TIGER IGNORE=Y TABLES=(EMP,DEPT) FULL=N
或 TABLES=(T1: P1,T1: P2),如果 T1 是分区表

USERID 必须是命令行中的第一个参数。

关键字 说明(默认)
----------------------------------------------
USERID 用户名/口令
FULL 导入整个文件 (N)
BUFFER 数据缓冲区大小
FROMUSER 所有人用户名列表
FILE 输入文件 (EXPDAT.DMP)
TOUSER 用户名列表
SHOW 只列出文件内容 (N)
TABLES 表名列表
IGNORE 忽略创建错误 (N)
RECORDLENGTH IO 记录的长度
GRANTS 导入权限 (Y)
INCTYPE 增量导入类型
INDEXES 导入索引 (Y)
COMMIT 提交数组插入 (N)
ROWS 导入数据行 (Y)
PARFILE 参数文件名
LOG 屏幕输出的日志文件
CONSTRAINTS 导入限制 (Y)
DESTROY 覆盖表空间数据文件 (N)
INDEXFILE 将表/索引信息写入指定的文件
SKIP_UNUSABLE_INDEXES 跳过不可用索引的维护 (N)
ANALYZE 执行转储文件中的 ANALYZE 语句 (Y)
FEEDBACK 显示每 x 行 (0) 的进度
TOID_NOVALIDATE 跳过指定类型 id 的校验
FILESIZE 各转储文件的最大尺寸
RECALCULATE_STATISTICS 重新计算统计值 (N)

下列关键字仅用于可传输的表空间
TRANSPORT_TABLESPACE 导入可传输的表空间元数据 (N)
TABLESPACES 将要传输到数据库的表空间
DATAFILES 将要传输到数据库的数据文件
TTS_OWNERS 拥有可传输表空间集中数据的用户


备份例子1:导出备份数据

#!/bin/bash

#=============================================#
# &n

[8] ...

正在看的ORACLE教程是:OracleEXP和IMP用法和介绍。bsp; 如果脚本用于crontab,下面Oracle环境变量必须设置 #
#=============================================#
ORACLE_BASE=/opt/oracle
ORACLE_HOME=$ORACLE_BASE/product/8.1.7
ORACLE_SID=oradb6
ORACLE_TERM=ansi
ORA_NLS33=$ORACLE_HOME/ocommon/nls/admin/data
NLS_LANG=American_America.ZHS16GBK
NLS_DATE_FORMAT=YYYYMMDDHH24MISS
LD_LIBRARY_PATH=$ORACLE_HOME/lib:$LD_LIBRARY_PATH
TMPDIR=/var/tmp
PATH=$PATH:$ORACLE_HOME/bin
export ORACLE_BASE ORACLE_HOME ORACLE_SID ORACLE_TERM ORA_NLS33 NLS_LANG
export NLS_DATE_FORMAT LD_LIBRARY_PATH TMPDIR PATH
#============================================#

BACKUPDIR=/oradata/backup; export BACKUPDIR
USER_PASSWD=dbuser/oracle

RESULTFILE=/export/home/oracle/log/result.log

cd $BACKUPDIR

[NextPage]


exp $USER_PASSWD log=$(date '+%Y%m%d').log file=$(date '+%Y%m%d').dmp owner=dbuser
buffer=4096000 rows=n
if [ $? != 0 ]
then
echo "`date` backup exp fail" >> $RESULTFILE
exit
fi

rm -f tables.txt
sqlplus -s $USER_PASSWD /null
set heading off;
set term off;
set echo off;
set pagesize 0;
set linesize 1000;
set trimspool on;
set trimout on;
set feedback off;
set colsep |;
spool tables.txt;
select table_name from user_tables;
spool off;
exit;
EOF

for table in $(cat tables.txt)
do
exp $USER_PASSWD log=${table}_$(date '+%Y%m%d').log file
=${table}_$(date '+%Y%m%d').dmp tables=$table direct=y
if [ $? != 0 ]
then
echo "`date` backup exp $table fail" >> $RESULTFILE
exit
fi
done

compress -f *.dmp

echo "`date` backup succeed" >> $RESULTFILE


备份例子2:联机日备份数据

#!/usr/local/bin/bash

first_msg()
{
echo "******************************************************"
echo " "
echo "The batch process BACKUP_DAILY is starting at [ 'date' ]"
echo "Excuting by LogName = [ $LOGNAME ]"
echo " "
}

final_msg()
{
echo " "
echo "The batch process BACKUP_DAILY completed at [ 'date' ]"
echo "Excuting by LogName = [ $LOGNAME ]"
echo ">>>>> Please Make 

[9] ...

正在看的ORACLE教程是:OracleEXP和IMP用法和介绍。; Sure That It Has Been Done Successfully, "
echo ">>>>> Otherwise You Must Re-do It."
echo " "
echo "*****************************************************"
}

#********************************
# Main *
#********************************
USER_PASSWD=system/system
ARCHIVE_DEST=/appl/oracle/oradata/orafe/arch
DEVICE=/dev/rmt/ctape1
TRC_FILE=$TRC/Z_JOB_BACKUP_DAILY
TMP_SQL=$TRC/backup_daily_tmp.sql
BACKUP_DEST=${BACKUP_PATH}/$(date '+%Y%m%d')
SUCCESS=0
FAIL=1

first_msg
mkdir -m 777 -p $BACKUP_DEST
if [ ! -d $BACKUP_DEST ]
then
echo "$BACKUP_DEST create fail"
exit
fi

[NextPage]

#*******************************
# backup archive log *
#*******************************
echo "=========================================="
echo "Backup archive log begin on [ 'date' ]"
echo "alter system archive log stop;" > $TMP_SQL
sqlplus -s $USER_PASSWD EOF
if [ $? != 0 ]
then
echo "alter archive log stop fail"
exit
fi
cd $ARCHIVE_DEST
FILE_QT='ls|grep -c "arch*"'
FILE='ls|grep "arch*"'

echo "alter system archive log start;" > $TMP_SQL
sqlplus -s $USER_PASSWD EOF
if [ $? != 0 ]
then
echo "alter archive log start fail"
exit
fi
if [ $FILE_QT != 0 ]
then
mv -f $FILE $BACKUP_DEST
cd $BACKUP_DEST
compress -f *
tar -cvf $DEVICE *
if [ $? != 0 ]
then
echo "tar to tape fail"
exit
fi
fi
echo "Backup archive log end on [ 'date' ]"
echo "=========================================="
final_msg

备份例子3:联机全库备份数据

#!/usr/local/bin/bash

first_msg()
{
echo "******************************************************"
echo " &nbs

[10] ...

正在看的ORACLE教程是:OracleEXP和IMP用法和介绍。p; "
echo "The batch process JOB_BACKUP_FULL is starting at [ 'date' ]"
echo "Excuting by LogName = [ $LOGNAME ]"
echo " "
}

final_msg()
{
echo " "
echo "The batch process JOB_BACKUP_FULL completed at [ 'date' ]"
echo "Excuting by LogName = [ $LOGNAME ]"
echo ">>>>> Please Make Sure That It Has Been Done Successfully, "
echo ">>>>> Otherwise You Must Re-do It."
echo " "
echo "******************************************************"
}

#**************************
#* backup_begin *
#**************************
backup_begin()
{
echo "alter tablespace $1 begin backup;" > $TMP_SQL
sqlplus -s $USER_PASSWD EOF
if [ $? != 0 ]
then
return $FAIL
fi
return $SUCCESS
}

#**************************
#* backup_end *
#**************************
backup_end()
{
echo "alter tablespace $1 end backup;" > $TMP_SQL
sqlplus -s $USER_PASSWD EOF
if [ $? != 0 ]
then
return $FAIL
fi
return $SUCCESS
}

#********************************
# Main *
#********************************
USER_PASSWD=system/system
BACKUP_DEST=$BACKUP_PATH/full
DEVICE=/dev/rmt/ctape1
BACKUP_CFG=$TRC/backup.cfg
TRC_FILE=$TRC/BACKUP_FULL
TMP_SQL=$TRC/backup_full_tmp.sql
SUCCESS=0
FAIL=1

first_msg
rm -f $BACKUP_CFG
sqlplus -s $USER_PASSWD /null
set heading off;
set term off;
set echo off;
set page

[11]

正在看的ORACLE教程是:OracleEXP和IMP用法和介绍。size 0;
set linesize 1000;
set trimspool on;
set trimout on;
set feedback off;
set colsep =;
spool $TRC/backup.spl;
select tablespace_name,file_name from dba_data_files order by tablespace_name,fi
le_name;
spool off;
exit
EOF
tr -d ' ' $BACKUP_CFG

rm -f $TRC_FILE
if [ ! -f $BACKUP_CFG ]
then
echo "备份配置文件缺失" >$TRC_FILE
echo "$BACKUP_CFG not found"
exit
fi
mkdir -m 777 -p $BACKUP_DEST
if [ ! -d $BACKUP_DEST ]
then
echo "备份目录创建失败" >$TRC_FILE
echo "$BACKUP_DEST create fail"
exit
fi
cd $BACKUP_DEST
rm -f *

#*******************************
# backup control file *
#*******************************
echo "=========================================="
echo "正在备份控制文件" > $TRC_FILE
echo "Backup control begin on [ 'date' ]"
echo "alter database backup controlfile to '$BACKUP_DEST/control.ctl';" > $TMP_SQL
sqlplus -s $USER_PASSWD EOF
if [ $? != 0 ]
then
echo "备份控制文件失败" > $TRC_FILE
echo "Backup control file fail"
exit
fi
echo "Backup control end on [ 'date' ]"

#*******************************
# backup tablespaces *
#*******************************
TABLESPACES='cut -d= -f1 $BACKUP_CFG|uniq'
for tablespace in $TABLESPACES
do
echo "=========================================="
echo "正在备份$tablespace" > $TRC_FILE
echo "Backup $tablespace begin on [ 'date' ]"
backup_begin $tablespace
if [ $? != 0 ]
then
echo "备份$tablespace失败" > $TRC_FILE
echo "Turn on backup option of $tablespace fail"
exit
fi
DATAFILES='awk -v var=$tablespace -F = '$1==var {print $2}' $BACKUP_CFG'
for datafile in $DATAFILES
do
 

[12]

正在看的ORACLE教程是:OracleEXP和IMP用法和介绍。; if [ ! -r $datafile ]
then
backup_end $tablespace
echo "备份$tablespace失败" > $TRC_FILE
echo "$tablespace:$datafile unreadable"
exit
fi
compress -c $datafile > $BACKUP_DEST/'basename $datafile'.Z
if [ $? != 0 ]
then
backup_end $tablespace
echo "备份$tablespace失败" > $TRC_FILE
echo "Backup $tablespace:$datafile fail"
exit
, fi
done
backup_end $tablespace
echo "Backup $tablespace end on [ 'date' ]"
done

#**************************
# tar files *
#**************************
echo "=========================================="
echo "正在备份至磁带" > $TRC_FILE
echo "tar to tape on [ 'date' ]"
cd $BACKUP_DEST
tar -cvf $DEVICE *
if [ $? != 0 ]
then
echo "备份至磁带失败" > $TRC_FILE
echo "tar to tape fail"
exit
fi
echo "tar to tape on [ 'date' ]"
echo "=========================================="

echo "全备份已完成" > $TRC_FILE
final_msg

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[13]

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MySQL functions can be used for data processing and calculation. 1. Basic usage includes string processing, date calculation and mathematical operations. 2. Advanced usage involves combining multiple functions to implement complex operations. 3. Performance optimization requires avoiding the use of functions in the WHERE clause and using GROUPBY and temporary tables.

An efficient way to batch insert data in MySQLAn efficient way to batch insert data in MySQLApr 29, 2025 pm 04:18 PM

Efficient methods for batch inserting data in MySQL include: 1. Using INSERTINTO...VALUES syntax, 2. Using LOADDATAINFILE command, 3. Using transaction processing, 4. Adjust batch size, 5. Disable indexing, 6. Using INSERTIGNORE or INSERT...ONDUPLICATEKEYUPDATE, these methods can significantly improve database operation efficiency.

Steps to add and delete fields to MySQL tablesSteps to add and delete fields to MySQL tablesApr 29, 2025 pm 04:15 PM

In MySQL, add fields using ALTERTABLEtable_nameADDCOLUMNnew_columnVARCHAR(255)AFTERexisting_column, delete fields using ALTERTABLEtable_nameDROPCOLUMNcolumn_to_drop. When adding fields, you need to specify a location to optimize query performance and data structure; before deleting fields, you need to confirm that the operation is irreversible; modifying table structure using online DDL, backup data, test environment, and low-load time periods is performance optimization and best practice.

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