SQL/MP Installation and Management Guide

Format 2 Partitions
HP NonStop SQL/MP Installation and Management Guide—523353-004
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Fallback Considerations
When you alter a partition (table or index) to Format 2, its label is changed to a
new format with expanded fields to allow for the larger attribute values that are
possible with Format 2 partitions.
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When all changes described in the previous item are made, you should take new
TMF online dumps or backups of the tables involved to establish their TMF file
recovery or backup protection. Include all the partitions of the involved tables, not
just the partitions that were altered to Format 2, in addition to all of their associated
index partitions and views and the SQL catalogs that were changed.
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Block headers in Format 2 partitions are larger than those in Format 1 partitions.
Because of this, you cannot alter to Format 2 the partitions of some tables whose
block size is close to the sum of their row size and the Format 1 block header size.
If you attempt to do this, the ALTER TABLE statement fails with SQL error 1221
and file system error 1096.
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If you introduce a Format 2-enabled table that is partitioned across multiple
systems, you must first migrate all affected systems to an RVU that supports this
feature.
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If you have any programs or third-party products that use TMFARLIB to read the
audit trail on your system, it is best to rebind these programs with the version of
TMFARLIB provided with RVUs that support SQL Format 2 partitions and to obtain
rebound versions of your third-party products.
You must use rebound versions of these programs or products, however, before
you introduce any Format 2-enabled tables that use the AUDITCOMPRESS option
on your system. The AUDITCOMPRESS option is the default when a SQL table is
created.
Fallback Considerations
This subsection describes three fallback scenarios. If any SQL Format 2-enabled
tables have been created on your system, HP recommends that you fall back using
Scenario 2, rather than Scenario 3, if at all possible.
Fallback Scenario 1
If you have not created any SQL Format 2-enabled tables on your system and no
version 350 SQL catalogs exist, no Format 2 fallback considerations apply, and you
are not restricted in your choice of fallback RVU. However, other fallback
considerations might still apply because of intervening RVUs that your fallback
bypassed or the use of other features introduced in these RVUs.
Fallback Scenario 2
If you have created any SQL Format 2-enabled tables on your system and you are
able to perform all these cleanup steps before falling back, no fallback considerations
apply, and you are not restricted in your choice of fallback RVU: