SQL/MP Installation and Management Guide

HP NonStop SQL/MP Installation and Management Guide—523353-004
C-1
C Format 2 Partitions
Format 2 enabling allows SQL/MP to support partitions of a size greater than 2
gigabytes (GB) and up to 1 terabyte (TB). The size of a partition is limited by the size of
the single disk upon which it resides.
This appendix discusses planning, migration, fallback, interoperability, and third party
considerations for using Format 2 partitions.
Planning for SQL Format 2-Enabled Tables and
Format 2 Partitions
Migration of Format 1 enabled tables to Format 2-enabled tables depends on:
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Application requirements
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Logical and physical database design
•
Hardware configuration
There are also limits you should consider when planning for SQL Format 2 partitions:
•
Partition size continues to be limited by the disk size.
•
Maximum extent sizes for Format 2 partitions have been increased.
•
The maximum number of extents for Format 2 partitions has been decreased.
•
The maximum row size is smaller because of a larger block header and record
offset size for Format 2 partitions.
•
The maximum number of rows that fit in a block is smaller because of a larger
block header and record offset for Format 2 partitions.
•
The maximum number of partitions is approximately 10 percent fewer for Format
2-enabled tables when compared to EXTENDED tables.
If your application has large databases and stringent downtime requirements, migration
might be more appropriate than conversion. Conversion is a separate offline operation,
while migration is a stepped refinement of the database as it moves from being a
Format 1 database to one that increasingly uses Format 2 partitions.
Conversion requires these steps:
1. Create a copy of the database schema in which requisite tables are Format
2-enabled and partitions of such tables and indexes are Format 2.
2. Stop all your applications and use SQLCI LOAD to copy data from the existing
Format 1 enabled tables to the newly created Format 2-enabled tables.
3. Replace the existing tables with each converted table.
4. Restart your applications.