HP NonStop RDF, Руководство по управлению

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• Partitioned files (key-sequenced or relative). For partitioned files, you can initiate the load
operation with a single command by executing the LOAD command against the primary
partition.
• Alternate key files (key-sequenced or relative). You should execute LOAD commands
against all alternate key files.
Special Consideration for Enscribe Files
If you create empty Enscribe files on your primary system, you should create them with the audit
attribute set off. This is particularly important if you create them on volumes protected by RDF.
If you create them as audited files on database volumes that are being protected by RDF, the
updaters also create them on the backup system. You then must purge the files on your backup
system before copying the loaded files from the primary system.
General Considerations for NonStop SQL Tables
• Key-sequenced tables without SYSKEY. To improve the performance of the load operations
significantly, specify the SORTED option.
• Tables with SYSKEY or Clustering Keys. Because the NonStop SQL load operations generate
new SYSKEY and clustering key values, do not use the create/load method to get a copy of
such table. Instead, use the method explained in Step 4, Method 2 under
“Synchronizing
Entire Databases Online” (page 168) .
• Relative tables. To ensure complete consistency with the source files, specify the NO
COMPACT option.
• Entry-sequenced tables. Do not use the create/load method to obtain a copy of
entry-sequenced files. Instead, use the method explained in Step 4, Method 2 under
“Synchronizing Entire Databases Online” (page 168) .
• Partitioned tables. You can initiate the load operation with a single command by executing
the LOAD command against the primary partition.
• Index tables. With regard to index tables, there are several considerations for relative and
key-sequenced tables. Regardless of base table type, you cannot load an index table by itself.
Index tables can only be loaded when the associated relative or key-sequenced table is
loaded.
If you want the associated index tables loaded when you load a relative or key-sequenced
table, you must create empty index tables first, before issuing the LOAD command. When
you load the base table, the index tables are loaded automatically.
Alternatively, you can load your base tables without index tables. Then you can create and
populate your index tables with the NonStop SQL product of choice before you start the
RDF updaters.
If you fail to create the index tables before issuing the START UPDATE command, the
affected updater reports a file-system error 11 (File not found) when trying to apply an
update to an index table, and it continues to retry the update. In this situation, the updater
does not make forward progress until you create the index on your backup system.
Enscribe Queue File Issues
For ENSCRIBE queue files, a different method of obtaining the fuzzy copy is required. You must
use the FUP COPY command with the SHARE option specified, and with “FIRST 1” specified.
For example, the following command copies the contents of file QUEUE1 to QUEUE2.
FUP COPY QUEUE1, QUEUE2, FIRST 1, SHARE
To ensure that your target file, QUEUE2 in the above example, has the proper content, copy the
content of the target file to the screen by using the following command:
FUP COPY QUEUE2,, H
172 Online Database Synchronization