SQL/MP Installation and Management Guide

The SQL/MP Database Management Environment
HP NonStop SQL/MP Installation and Management Guide—523353-004
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SQL/MP Features
not recompile a program explicitly, an SQL recompilation occurs automatically before
each execution of the program to ensure it uses the current definition of the table.
SQL/MP Features
The SQL/MP RDBMS supports:
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Distributed databases
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Database protection and recovery
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Data integrity
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Multiple character sets, including single-byte and double-byte data
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DEFINEs
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Database security
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Parallel processing
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High availability
Distributed Databases
You can distribute an SQL/MP database across multiple nodes with complete
transparency, location independence, read and update capability, and data integrity.
Objects in the same database can reside on different nodes. The partitions of a table or
index can be spread across nodes as well, with the partitioning invisible to users.
Local autonomy guarantees that local processing is not affected by unreliable
communications links. This autonomy is facilitated by an active, distributed data
dictionary and a feature that opens partitions of a database only when demanded by a
query. Also, automatic recompilation is invoked to rebind plans when certain resources
are unavailable.
A distributed database can be managed by a central site, by each independent
distributed site, or by a combination of these. For more information, see Section 12,
Managing a Distributed Database.
Database Protection and Recovery
An SQL/MP database is protected by the TMF subsystem, which provides automatic
online recovery of audited SQL objects and files by using audit trails. A transaction in
progress can be aborted when a failure or error condition is detected. The TMF
subsystem terminates the transaction and restores the database to its state before the
beginning of the transaction. The TMF subsystem provides two additional recovery
mechanisms:
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Volume recovery, which recovers the database in the event of a disk crash or
system failure