Shulou(Shulou.com)06/01 Report--

1.Data Pump characteristics

(1) support parallel processing of import and export tasks

(2) support pausing and restarting import and export tasks

(3) support importing or exporting objects in remote database through database link.

(4) support automatic modification of object owner, data file or tablespace during import through REMAP_SCHEMA, REMAP_DATAFILE, REMAP_TABLESPACE parameters.

(5) very fine-grained object control is provided during export and import. Imp/exp controls at most whether to import limited object types such as indexes, constraints, authorization information, etc. In data pump, it can not only be accurate to the object type, but also specify in detail whether an object is included or not through the two parameters of include or exclude.

2.Data Pump rule

When you specify a file through the DUMPFILE parameter, you specify not the local detailed path, but the file name, and the IMPDP and EXPDP commands have another parameter called DIRECTORY to specify the path where the dump file is located. Note that the DIRECTORY parameter does not directly specify the local disk path, but rather the directory object in the Oracle database.

The Directory object is a point to a path in the operating system. Each directory object has two permissions of read/write, which can be granted to specified users and roles through the grant command. Users with read/write permissions on the directory object can read and write files under the operating system path specified by the directory object.

Using the 3.DIRECTORY object

Step 1: query the existing directory

SQL > select * from dba_directories

OWNER DIRECTORY_NAME DIRECTORY_PATH

SYS DATA_PUMP_DIR / u01/app/oracle/admin/orcl/dpdump/

Step two, create a new directory

SQL > create directory dump_file_dir as'/ backup/dump/'

The third step is to authorize the new directory

SQL > grant read,write on directory dump_file_dir to scott

OK, now the newly created directory is ready to use

4. Calling mode

Like exp, expdp calls support both command line and parameter file calls

(1) call the command line

Direct execution of orders

For example: $expdp scott/tiger tables=emp directory=dump_dir dumpfile=scott_emp.dmp log=scott_emp.log

(2) call by parameter file

First, edit a file

$vi scott_emp.dat

Directory=dump_dir

Tables=emp

Buffer=20480

Log=scott_emp.log

The second step, and then invoke this file when the command is executed

$expdp scott/tiger parfile=scott_emp.dat

5. Give examples to illustrate

(1) full library export

$expdp sys/oracle directory=dump_file_dir logfile=database_full.dmp logfile=database_full.log full=y

(2) Export in parallel mode

Parallel export takes the parallel parameter. Note that when using this parameter, when the amount of data is very large, it can play a positive role, when the amount of data is very small, the parallel parameter will be counterproductive.

$expdp sys/oracle directory=dump_file_dir logfile=database_full.dmp logfile=database_full.log parallel=3

(3) Export all tables of scott users

$expdp scott/tiger directory=dump_file_dir logfile=scott_tables.dmp logfile=scott_tables.log

6. Important parameters

DIRECTORY: specify parameter

DUMPFILE: specify the output file name

LOGFILE: specify output log

FILESIZE: specify the size of the exported file

PARALLEL: parallel import

Data filtering

QUERY: filtering data

SAMPLE: percentage filtering [SAMPLE=A:30]

EXCLUDE: excluding object

INCLUDE: including object

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