SQL/MX 2.x Reference Manual (H06.04+)

SQL/MX Utilities
HP NonStop SQL/MX Reference Manual—540440-003
5-8
Considerations for DUP
Considerations for DUP
•
You must have all privileges for the source table and own the schema where the
target table will reside or be the super ID.
•
Referential integrity constraints and triggers are ignored.
•
The source table can exist on a remote node and be referenced by the current
DUP operation if the remote node is visible to the local node. The target table can
also exist in a catalog and schema that reside on a visible remote node.
•
DUP does not check disk space before running the request. You must confirm that
enough disk space is available before running the DUP request.
•
DUP displays errors if the source table or target table and its dependent indexes
cannot be accessed, or if the load fails in response to a resource or file system
problem.
You must run the RECOVER utility to clean up the failed DUP operation. If the
DUP operation fails after all of the data has been successfully copied to the target
objects, specify RECOVER with the RESUME option to complete the DUP
operation. If the DUP operation fails before the data is successfully copied, specify
RECOVER with the CANCEL option to roll back the DUP operation. This status
can be found by reading the DDL_LOCK table. If you run the RECOVER operation
with the incorrect option, RECOVER displays an error message so you can rerun it
with the correct option. For details, see Checking File Locks on page 5-3.
No restart facility is available to handle partially copied data.
•
During the DUP operation, the target table is marked as corrupt to prevent other
processes from viewing the data until the operation completes successfully.
•
All utility operations have the potential to run for hours, especially those that
involve a great deal of data movement. To manage systems effectively, you need
to know how far the operation has proceeded and how much longer it needs to run.
Utilities provide progress reports that indicate what step is in progress. Utility
operations periodically place progress reports in the metadata tables through the
DDL lock mechanism. You can examine the metadata to get the latest information.
These reports are referred to as the operation's progress. The DUP operation has
the option to log these progress reports to an OSS text file.
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DDL locks
Many utility operations run in multiple TMF transactions. As a result, conflicting
operations that change metadata and label information affecting the outcome
of the utility are executed concurrently.
Caution. If you chose the PURGE option for TARGET, DUP first drops the target table. If an
error occurs further along in the DUP operation, you cannot recover the original target table.
Back up the target table before you begin your DUP operation.