Wednesday, January 18, 2012

Oracle

Oracle Data Pump in Oracle Database 10g (expdp and impdp)

Getting Started

For the examples to work we must first unlock the SCOTT account and create a directory object it can access. The directory object is only a pointer to a physical directory, creating it does not actually create the physical directory on the file system.
CONN / AS SYSDBA
ALTER USER scott IDENTIFIED BY tiger ACCOUNT UNLOCK;

CREATE OR REPLACE DIRECTORY test_dir AS '/u01/app/oracle/oradata/';
GRANT READ, WRITE ON DIRECTORY test_dir TO scott;
Existing directories can be queried using the ALL_DIRECTORIES view.

Table Exports/Imports

The TABLES parameter is used to specify the tables that are to be exported. The following is an example of the table export and import syntax.
expdp scott/tiger@db10g tables=EMP,DEPT directory=TEST_DIR dumpfile=EMP_DEPT.dmp logfile=expdpEMP_DEPT.log

impdp scott/tiger@db10g tables=EMP,DEPT directory=TEST_DIR dumpfile=EMP_DEPT.dmp logfile=impdpEMP_DEPT.log
For example output files see expdpEMP_DEPT.log and impdpEMP_DEPT.log.
The TABLE_EXISTS_ACTION=APPEND parameter allows data to be imported into existing tables.

Schema Exports/Imports

The OWNER parameter of exp has been replaced by the SCHEMAS parameter which is used to specify the schemas to be exported. The following is an example of the schema export and import syntax.
expdp scott/tiger@db10g schemas=SCOTT directory=TEST_DIR dumpfile=SCOTT.dmp logfile=expdpSCOTT.log

impdp scott/tiger@db10g schemas=SCOTT directory=TEST_DIR dumpfile=SCOTT.dmp logfile=impdpSCOTT.log
For example output files see expdpSCOTT.log and impdpSCOTT.log.

Database Exports/Imports

The FULL parameter indicates that a complete database export is required. The following is an example of the full database export and import syntax.
expdp system/password@db10g full=Y directory=TEST_DIR dumpfile=DB10G.dmp logfile=expdpDB10G.log

impdp system/password@db10g full=Y directory=TEST_DIR dumpfile=DB10G.dmp logfile=impdpDB10G.log
For an example output file see expdpDB10G.log.

INCLUDE and EXCLUDE

The INCLUDE and EXCLUDE parameters can be used to limit the export/import to specific objects. When the INCLUDE parameter is used, only those objects specified by it will be included in the export/import. When the EXCLUDE parameter is used, all objects except those specified by it will be included in the export/import. The two parameters are mutually exclusive, so use the parameter that requires the least entries to give you the result you require. The basic syntax for both parameters is the same.
INCLUDE=object_type[:name_clause] [, ...]
EXCLUDE=object_type[:name_clause] [, ...]
The following code shows how they can be used as command line parameters.
expdp scott/tiger@db10g schemas=SCOTT include=TABLE:"IN ('EMP', 'DEPT')" directory=TEST_DIR dumpfile=SCOTT.dmp logfile=expdpSCOTT.log

expdp scott/tiger@db10g schemas=SCOTT exclude=TABLE:"= 'BONUS'" directory=TEST_DIR dumpfile=SCOTT.dmp logfile=expdpSCOTT.log
If the parameter is used from the command line, depending on your OS, the special characters in the clause may need to be escaped, as follows. Because of this, it is easier to use a parameter file.
include=TABLE:\"IN (\'EMP\', \'DEPT\')\"
A single import/export can include multiple references to the parameters, so to export tables, views and some packages we could use either of the following approaches.
INCLUDE=TABLE,VIEW,PACKAGE:"LIKE '%API'"

or

INCLUDE=TABLE
INCLUDE=VIEW
INCLUDE=PACKAGE:"LIKE '%API'"
The valid object type paths that can be included or excluded can be displayed using the DATABASE_EXPORT_OBJECTS, SCHEMA_EXPORT_OBJECTS, and TABLE_EXPORT_OBJECTS views.

Network Exports/Imports (NETWORK_LINK)

The NETWORK_LINK parameter identifies a database link to be used as the source for a network export/import. The following database link will be used to demonstrate its use.
CONN / AS SYSDBA
GRANT CREATE DATABASE LINK TO test;

CONN test/test
CREATE DATABASE LINK remote_scott CONNECT TO scott IDENTIFIED BY tiger USING 'DEV';
In the case of exports, the NETWORK_LINK parameter identifies the database link pointing to the source server. The objects are exported from the source server in the normal manner, but written to a directory object on the local server, rather than one on the source server. Both the local and remote users require the EXP_FULL_DATABASE role granted to them.
expdp test/test@db10g tables=SCOTT.EMP network_link=REMOTE_SCOTT directory=TEST_DIR dumpfile=EMP.dmp logfile=expdpEMP.log
For imports, the NETWORK_LINK parameter also identifies the database link pointing to the source server. The difference here is the objects are imported directly from the source into the local server without being written to a dump file. Although there is no need for a DUMPFILE parameter, a directory object is still required for the logs associated with the operation. Both the local and remote users require the IMP_FULL_DATABASE role granted to them.
impdp test/test@db10g tables=SCOTT.EMP network_link=REMOTE_SCOTT directory=TEST_DIR logfile=impdpSCOTT.log remap_schema=SCOTT:TEST

impdp

impdp help=y

Import: Release 10.1.0.2.0 - Production on Saturday, 11 September, 2004 17:22

Copyright (c) 2003, Oracle.  All rights reserved.


The Data Pump Import utility provides a mechanism for transferring data objects
between Oracle databases. The utility is invoked with the following command:

     Example: impdp scott/tiger DIRECTORY=dmpdir DUMPFILE=scott.dmp

You can control how Import runs by entering the 'impdp' command followed
by various parameters. To specify parameters, you use keywords:

     Format:  impdp KEYWORD=value or KEYWORD=(value1,value2,...,valueN)
     Example: impdp scott/tiger DIRECTORY=dmpdir DUMPFILE=scott.dmp

USERID must be the first parameter on the command line.

Keyword               Description (Default)
------------------------------------------------------------------------------
ATTACH                Attach to existing job, e.g. ATTACH [=job name].
CONTENT               Specifies data to load where the valid keywords are:
                      (ALL), DATA_ONLY, and METADATA_ONLY.
DIRECTORY             Directory object to be used for dump, log, and sql files.
DUMPFILE              List of dumpfiles to import from (expdat.dmp),
                      e.g. DUMPFILE=scott1.dmp, scott2.dmp, dmpdir:scott3.dmp.
ESTIMATE              Calculate job estimates where the valid keywords are:
                      (BLOCKS) and STATISTICS.
EXCLUDE               Exclude specific object types, e.g. EXCLUDE=TABLE:EMP.
FLASHBACK_SCN         SCN used to set session snapshot back to.
FLASHBACK_TIME        Time used to get the SCN closest to the specified time.
FULL                  Import everything from source (Y).
HELP                  Display help messages (N).
INCLUDE               Include specific object types, e.g. INCLUDE=TABLE_DATA.
JOB_NAME              Name of import job to create.
LOGFILE               Log file name (import.log).
NETWORK_LINK          Name of remote database link to the source system.
NOLOGFILE             Do not write logfile.
PARALLEL              Change the number of active workers for current job.
PARFILE               Specify parameter file.
QUERY                 Predicate clause used to import a subset of a table.
REMAP_DATAFILE        Redefine datafile references in all DDL statements.
REMAP_SCHEMA          Objects from one schema are loaded into another schema.
REMAP_TABLESPACE      Tablespace object are remapped to another tablespace.
REUSE_DATAFILES       Tablespace will be initialized if it already exists (N).
SCHEMAS               List of schemas to import.
SKIP_UNUSABLE_INDEXES Skip indexes that were set to the Index Unusable state.
SQLFILE               Write all the SQL DDL to a specified file.
STATUS                Frequency (secs) job status is to be monitored where
                      the default (0) will show new status when available.
STREAMS_CONFIGURATION Enable the loading of Streams metadata
TABLE_EXISTS_ACTION   Action to take if imported object already exists.
                      Valid keywords: (SKIP), APPEND, REPLACE and TRUNCATE.
TABLES                Identifies a list of tables to import.
TABLESPACES           Identifies a list of tablespaces to import.
TRANSFORM             Metadata transform to apply (Y/N) to specific objects.
                      Valid transform keywords: SEGMENT_ATTRIBUTES and STORAGE.
                      ex. TRANSFORM=SEGMENT_ATTRIBUTES:N:TABLE.
TRANSPORT_DATAFILES   List of datafiles to be imported by transportable mode.
TRANSPORT_FULL_CHECK  Verify storage segments of all tables (N).
TRANSPORT_TABLESPACES List of tablespaces from which metadata will be loaded.
                      Only valid in NETWORK_LINK mode import operations.
VERSION               Version of objects to export where valid keywords are:
                      (COMPATIBLE), LATEST, or any valid database version.
                      Only valid for NETWORK_LINK and SQLFILE.

The following commands are valid while in interactive mode.
Note: abbreviations are allowed

Command               Description (Default)11g
------------------------------------------------------------------------------
CONTINUE_CLIENT       Return to logging mode. Job will be re-started if idle.
EXIT_CLIENT           Quit client session and leave job running.
HELP                  Summarize interactive commands.
KILL_JOB              Detach and delete job.
PARALLEL              Change the number of active workers for current job.
                      PARALLEL=.
START_JOB             Start/resume current job.
                      START_JOB=SKIP_CURRENT will start the job after skipping
                      any action which was in progress when job was stopped.
STATUS                Frequency (secs) job status is to be monitored where
                      the default (0) will show new status when available.
                      STATUS=[interval]
STOP_JOB              Orderly shutdown of job execution and exits the client.
                      STOP_JOB=IMMEDIATE performs an immediate shutdown of the
                      Data Pump job.
Oracle 10g Release 2 (10.2) added the following parameter.
Keyword               Description (Default)
------------------------------------------------------------------------------
ENCRYPTION_PASSWORD   Password key for accessing encrypted column data.
                      This parameter is not valid for network import jobs.
Oracle 11g Release 1 (11.1) added the following parameters.
Keyword               Description (Default)
------------------------------------------------------------------------------
DATA_OPTIONS          Data layer flags where the only valid value is:
                      SKIP_CONSTRAINT_ERRORS-constraint errors are not fatal.
PARTITION_OPTIONS     Specify how partitions should be transformed where the
                      valid keywords are: DEPARTITION, MERGE and (NONE)
REMAP_DATA            Specify a data conversion function,
                      e.g. REMAP_DATA=EMP.EMPNO:REMAPPKG.EMPNO
Oracle 11g Release 1 (11.2) altered the format of the help output as well as adding the following parameters.
CLUSTER
Utilize cluster resources and distribute workers across the Oracle RAC.
Valid keyword values are: [Y] and N.

SERVICE_NAME
Name of an active Service and associated resource group to constrain Oracle RAC resources.

SOURCE_EDITION
Edition to be used for extracting metadata.

TARGET_EDITION
Edition to be used for loading metadata.