Oracle Data UnLoader (DUL) Update

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I first learned to use DUL about 10 years ago from an in-class workshop conducted by Jim Stone. While
the primary purpose and use of Bernard Van Duijnen’s DUL data extract utility has not changed, a recent
customer incident had me review its’ capabilities and what has changed specifically over the last few
years. Others in ACS who don’t use it often should be aware of the following:
Documentation: The technical support and download website was updated to

https://stbeehive.oracle.com/teamcollab/overview/DUL.

This should be your first stop for technicalinformation. The User’s Configuration Guide while still very primitive, is now easily downloadable to a Word document and is updated to reflect the current release of DUL. Wiki pages now exist organized by topic to extend the User’s Guide. Additionally, there is a Forum created to collect War Stories and Help.
The long-time distribution list helpdul_nl@oracle.com is still available for real-time help.
Configuration: To run DUL, 2 configuration files are needed; init.dul and control.dul. While init.dul
specifies the platform specific parameters, control.dul specified the location of the datafiles for DUL to
extract from. In the past, control.dul had required a file number, the relative file number and the fully
qualified datafile name. This required asking the customer to run a SQL statement with the database in
mount-only mode which often delayed the engagement and in many cases would not even be possible.
Now, if the database is 10 or greater, DUL can read the file number and relative file numbers directly
from the header (assuming they aren’t corrupted) making the specification unnecessary in the
control.dul. There are also options now for specifying Automatic Storage Managed (ASM) disks as input.
See the Configuration Guide for details.
Database Features: The current version of DUL is 10.2.4.27 as of this writing. While DUL will run against
an Oracle 11g database, there are some 11g features or data types that are not currently supported:
11g secure file lobs, label security, encryption, ASM on Exadata. For a full list, see the above web URL.
With the above in mind, each DUL engagement will have its’ own challenges. No two are necessarily
alike. It’s important to set customer expectations ahead and set limits on what is defined as success.
Performing a DUL used to be a fixed, high cost, onsite-required service. Some Support Analysts still
reference it that way in SRs. However, it is now a Time and Materials, mostly remote service billed at
standard rates which makes it more likely that a customer will be willing to move ahead.
To perform the service remotely (via OWC or WebEx) requires sending the customer the 600k DUL
executable. As this is an internal-only utility, the legal requirement is that the customer must delete the
executable from their systems once completed. While this may be difficult to enforce, the DUL
executable will expire after some time and put out a message saying “A new version of DUL is required”.
To be prudent, always download the latest version from the website just before engaging. As Bernard is
often quoted, “Life is DUL without it!”

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