Why are directory objects needed?
They are needed to ensure data security and integrity. Otherwise, users would be able to read data that they should not have access to and perform unwarranted operations on the server.
What makes Data Pump faster than original Export and Import?
There are three main reasons that Data Pump is faster than original Export and Import. First, the Direct Path data access method (which permits the server to bypass SQL and go right to the data blocks on disk) has been rewritten to be much more efficient and now supports Data Pump Import and Export.
Second, because Data Pump does its processing on the server rather than in the client, much less data has to be moved between client and server.
Finally, Data Pump was designed from the ground up to take advantage of modern hardware and operating system architectures in ways that original Export/ and Import cannot. These factors combine to produce significant performance improvements for Data Pump over original Export and Import
How much faster is Data Pump than the original Export and Import utilities?
For a single stream, Data Pump Export is approximately 2 times faster than original Export
and Data Pump Import is approximately 15 to 40 times faster than original Import. Speed
can be dramatically improved using the PARALLEL parameter.
Why is Data Pump slower on small jobs?
Data Pump was designed for big jobs with lots of data. Each Data Pump job has a master
table that has all the information about the job and is needed for restartability. The overhead
of creating this master table makes small jobs take longer, but the speed in processing large
amounts of data gives Data Pump a significant advantage in medium and larger jobs.
Are original Export and Import going away?
Original Export is being deprecated with the Oracle Database 11g release. Original Import
will always be supported so that dump files from earlier releases (release 5.0 and later) will be able to be imported. Original and Data Pump dump file formats are not compatible.
Are Data Pump dump files and original Export and Import dump files compatible?
No, the dump files are not compatible or interchangeable. If you have original Export dump
files, you must use original Import to load them.
How can I monitor my Data Pump jobs to see what is going on?
In interactive mode, you can get a lot of detail through the STATUS command.
In SQL, you can query the following views:
• DBA_DATAPUMP_JOBS - all active Data Pump jobs and the state of each job
• USER_DATAPUMP_JOBS – summary of the user’s active Data Pump jobs
• DBA_DATAPUMP_SESSIONS – all active user sessions that are attached to a Data Pumpjob
• V$SESSION_LONGOPS – shows all progress on each active Data Pump job
Can I use Oracle Enterprise Manager with Data Pump?
Yes, OEM supports a fully functional interface to Data Pump.
Can I use gzip with Data Pump?
They are needed to ensure data security and integrity. Otherwise, users would be able to read data that they should not have access to and perform unwarranted operations on the server.
What makes Data Pump faster than original Export and Import?
There are three main reasons that Data Pump is faster than original Export and Import. First, the Direct Path data access method (which permits the server to bypass SQL and go right to the data blocks on disk) has been rewritten to be much more efficient and now supports Data Pump Import and Export.
Second, because Data Pump does its processing on the server rather than in the client, much less data has to be moved between client and server.
Finally, Data Pump was designed from the ground up to take advantage of modern hardware and operating system architectures in ways that original Export/ and Import cannot. These factors combine to produce significant performance improvements for Data Pump over original Export and Import
How much faster is Data Pump than the original Export and Import utilities?
For a single stream, Data Pump Export is approximately 2 times faster than original Export
and Data Pump Import is approximately 15 to 40 times faster than original Import. Speed
can be dramatically improved using the PARALLEL parameter.
Why is Data Pump slower on small jobs?
Data Pump was designed for big jobs with lots of data. Each Data Pump job has a master
table that has all the information about the job and is needed for restartability. The overhead
of creating this master table makes small jobs take longer, but the speed in processing large
amounts of data gives Data Pump a significant advantage in medium and larger jobs.
Are original Export and Import going away?
Original Export is being deprecated with the Oracle Database 11g release. Original Import
will always be supported so that dump files from earlier releases (release 5.0 and later) will be able to be imported. Original and Data Pump dump file formats are not compatible.
Are Data Pump dump files and original Export and Import dump files compatible?
No, the dump files are not compatible or interchangeable. If you have original Export dump
files, you must use original Import to load them.
How can I monitor my Data Pump jobs to see what is going on?
In interactive mode, you can get a lot of detail through the STATUS command.
In SQL, you can query the following views:
• DBA_DATAPUMP_JOBS - all active Data Pump jobs and the state of each job
• USER_DATAPUMP_JOBS – summary of the user’s active Data Pump jobs
• DBA_DATAPUMP_SESSIONS – all active user sessions that are attached to a Data Pumpjob
• V$SESSION_LONGOPS – shows all progress on each active Data Pump job
Can I use Oracle Enterprise Manager with Data Pump?
Yes, OEM supports a fully functional interface to Data Pump.
Can I use gzip with Data Pump?
Because Data Pump uses parallel operations to achieve its high performance, you cannot pipe
the output of Data Pump export through gzip. Starting in Oracle Database 11g, the COMPRESSION parameter can be used to compress a Data Pump dump file as it is being created. The COMPRESSION parameter is available as part of the Advanced Compression Option for Oracle Database 11g.
What are the modes of original Export and Import?
The Export and Import utilities support four modes of operation:
Full: Exports and imports a full database. Only users with the EXP_FULL_DATABASE and IMP_FULL_DATABASE roles can use this mode. Use the FULL parameter to specify this mode.
Tablespace: Enables a privileged user to move a set of tablespaces from one Oracle database to another. Use the TRANSPORT_TABLESPACE parameter to specify this mode.
User: Enables you to export and import all objects that belong to you (such as tables, grants, indexes, and procedures). A privileged user importing in user mode can import all objects in the schemas of a specified set of users. Use the OWNER parameter to specify this mode in Export, and use the FROMUSER parameter to specify this mode in Import.
Table: Enables you to export and import specific tables and partitions. A privileged user can qualify the tables by specifying the schema that contains them. Use the TABLES parameter to specify this mode.
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