SQL/MX 2.x Installation and Management Guide (G06.24+, H06.03+)

Planning Database Security and Recovery
HP NonStop SQL/MX Installation and Management Guide—523723-004
5-20
Using TMF In Recovery Operations
These commands and statements make up a complete user-defined TMF
transaction:
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BEGIN WORK;
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SELECT...;
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INSERT...;
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DELETE...;
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COMMIT WORK;
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For many utility statements, the utility operation generates the appropriate number
of TMF transactions for the operation, reducing the overhead associated with TMF
audit trails and ensuring that the necessary locks are acquired for the operations.
These operations do not allow or do not recommend using user-defined TMF
transactions and work the same way regardless of the value of AUTOCOMMIT.
Utilities include DUP, MODIFY, POPULATE INDEX, PURGEDATA, RECOVER,
and UPDATE STATISTICS.
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It is not recommended that user-defined transaction be started certain for DDL
operations including CREATE INDEX, ALTER TABLE ADD CONSTRAINT, ALTER
TABLE ADD COLUMN, compound CREATE SCHEMA, or DROP SCHEMA.
•
Only one user-defined TMF transaction can be active at a time in an MXCI
session. You must commit or roll back the current user-defined transaction before
starting another.
Using TMF In Recovery Operations
All SQL/MX files are audited by TMF. Therefore TMF provides the most
comprehensive and robust means of recovery. With TMF volume recovery and file
recovery mechanisms, you can recover SQL/MX catalogs and objects after a system
or disk volume failure. You can also use file recovery to recover a dropped object or a
database to a specified time. These recovery operations, and others, are described
next. For additional information about volume recovery and file recovery, see the TMF
Operations and Recovery Guide.
Using TMF to Recover Dropped SQL/MX Objects
TMF is your primary means of recovering dropped SQL/MX objects. For specific
recovery procedures, see:
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Recovering Range Partitions on page 12-7
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Recovering SPJs on page 12-8
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Recovering Tables on page 12-8
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Recovering Views and Indexes on page 12-21