Oracle data pump

2
What is Data Pump?
 A replacement of the traditional export/import utilities?
 The evolution of the traditional export/import utilities?
 A completely new 10g utility serving a similar yet
slightly different purpose?

3
Other Options for Moving Data
 Traditional Export and Import
Pros
 Easy to use – most DBAs have years of experience using these
utilities
 Versatile – various options available; can specify what to include
 Platform independent
 Serial output
Cons
 Comparatively slow
 Can be network intensive
 Non-interruptible / resumable
 Limited filtering options (for example, can exclude just VIEWS)
 Limited remapping options (i.e. from one tablespace to another)

4
Other Options for Moving Data
 Transportable Tablespaces
Pros
 Undoubtedly the fastest way to move data
 Can use the traditional exp/imp or Data Pump to move meta-data
 Cross-platform support if the platform byte-order is the same
Cons
 Tablespaces must be made read-only
 Not selective (must move the entire tablespace)
 Flashback is not possible (tablespace is read only when copied)
 No physical reorganization is performed
 Datafile sizes remain constant
 Must use RMAN to convert the datafile if migrating to a platform with
a different byte-order (check V$TRANSPORTABLE_PLATFORM)

5
Other Options Used Less Frequently
 Extraction to a flat file and loading using SQL Loader
 Direct copy using database links (SQL Plus COPY
command)
 Oracle Streams
 3rd
Party data ETL or reorg tools

6
Top 10 Reasons to Love DataPump
10. Similar look and feel to the old exp/imp
9. Can filter on the full range of object types
8. Can re-map datafiles and or tablespaces on import
7. Estimates the export file size (space needed)
6. Parallelizable
5. Significantly faster than the traditional exp/imp
4. PL/SQL Interface – programmable
3. A file is not actually required - can import through a
network link
2. Track in v$session_longops
1. Resumable (interruptible and restartable)

7
Top 10 Reasons Not to Love Data Pump
10. Still generates redo (unlike direct path inserts)
9. Aggregation of exported data is not possible (sort only)
8. Performance on the server
7. Harder to tell what it’s doing at any given time
6. No equivalent to the STATISTICS option
5. Cannot be used with sequential media such as tapes and
pipes (not read/written serially)
4. Only accesses files on the server, never the client
3. Oracle directories are required in the DB to access the files
2. Does not support COMMIT on imp or CONSISTENT on exp
1. If constraints are violated on import, the load is discontinued

8
Operation Fundamentals
 Export/Import
These utilities would basically connect to the Oracle database
via Oracle NET and run queries or DDL/DML
Processing of returned results and I/O operations were done
on the client
 Data Pump
The executables call PL/SQL APIs
Therefore processing is done on the database server
This can be an advantage or a disadvantage depending on the
situation
“Self-Tuning”: no longer need to use BUFFER or RECORDSET

9
Export Operation
Network
Export
File(s)
exp.exe
Oracle
Database

10
Data Pump Export Operation
Network
Export
File(s)
expdp.exe
Oracle
Database

11
Key Differences
 Dump and log files are on the server, not the client
 Must have a DIRECTORY created in the Oracle
database for I/O
Permissions for the userid connecting to the instance, not the
schemas being exported or imported
 Canceling the client process does not stop the job
 Doesn’t automatically overwrite dump file if it already
exists – returns an error instead
 Parameters (command line) are reported in the log file
 Exported objects order based on table size
(descending) instead of alphabetically

12
Multiple Interfaces
1. Command line utilities expdb and impdb
 Similar to the familiar exp and imp in usage
 Use HELP=Y for a list of commands
 Oracle documentation provides a comparison table to exp/imp
1. Enterprise Manager
2. PL/SQL
 Can be used independently but is difficult
 All of these call the DBMS_DATAPUMP API
 Uses Oracle Advanced Queuing
 Uses DBMS_METADATA

13
Unload Mechanisms
 Data Pump automatically chooses to unload data either
using:
Direct path
External Tables (new driver called ORACLE_DATAPUMP)
 Same “External Tables” mechanism that was introduced in
Oracle9i
 When will it use External tables:
When parallelism can be used
When the table contains a complex data type or structure that
prevents direct path unloads
 A lot of tables fall under this situation – see Oracle documentation for a
complete list
 It doesn’t really matter to us which method is used

14
Multiple Processes
 Master Control Process
Spawns worker processes
Populates the master control table and log file
The master control table can be queried to track the job’s
process
At the end of an export, the master control table is written to
the dump file and dropped from the database
 Worker Processes
Performs the loading/unloading
Number of processes depends on the degree of parallelism
(the PARALLEL option)

15
Detaching and Re-Attaching
 Issuing “Ctrl-C” from the data pump import will
detach
Import is running on the server so it will continue
Brings you into “interactive-command” mode
 To re-attach, run impdp with the ATTACH= option
Example: impdp userid=system/oracle attach=JOB_01
Brings you back into “interactive-command” mode

16
New Views
 DBA_DATAPUMP_JOBS and USER_DATABASE_JOBS
Identify all jobs regardless of their state
Identify any master tables not associated with an active job
 DBA_DATAPUMP_SESSIONS
Identify user sessions that are attached to a job
 Data pump sessions populate v$session_longops
Documentation says that it is 100% accurate for imports but
testing proves otherwise!!!

17
Security Considerations
 Still uses the EXP_FULL_DATABASE and
IMP_FULL_DATABASE
 A privileged user will have these two roles
 A privileged user can:
Export/import objects owned by other schemas
Export non-schema objects (metadata)
Attach to, monitor, and control jobs initiated by others
Perform schema, datafile, and tablespace remapping
 Similar to the traditional export/import
 Supports label security
If exporting user has the EXEMPT ACCESS POLICY role

18
Object Statistics
 From Oracle documentation regarding data pump
exports:
“A parameter comparable to STATISTICS is not needed.
Statistics are always saved for tables.”
 From Oracle documentation regarding data pump
imports:
“A parameter comparable to STATISTICS is not needed. If the
source table has statistics, they are imported.”

19
Other Random Points
 Can still use a parameter file and the PARFILE
command line option
 Fully supports Automatic Storage Management (ASM)
 Can still flashback to a specified time or SCN
 Can still extract (or backup) DDL (meta data)
Using the SQLFILE option instead of the traditional
INDEXFILE or SHOW options
 Full support of LOBS

Oracle data pump

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Oracle data pump