Download (direct link):
• COPY moves data from an archived file to the same or a different Teradata system, and can create new tables if they do not already exist in the target database. Also, you can change the creator name of a restored table.
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Chapter 8: Archiving, Restoring and Recovering Data
Archive/Recovery (ARC) Utility
How ARC Works
ARC creates files when you archive databases, individual data tables, or permanent journal tables from the Teradata RDBMS. You input these files to ARC when you restore databases, individual data tables, or permanent journal tables back to the Teradata RDBMS.
ARC includes recovery with rollback and rollforward functions for data tables defined with, or stored in a database defined with, the JOURNAL option. Also, you can use a checkpoint to synchronize journals across all AMPs, and you can delete selected portions of a journal. However, take into consideration that:
• When a journal roll operation stops, all changes to that point are backed out.
• Permanent journals are not supported across an AMP reconfiguration. Rollforward or rollback operations terminate if there is a change in the hash maps for primary, fallback, or backup rows.
• Permanent journals are not supported across certain DDL statements. SQL operations that may prevent a rollforward or rollback operation from passing that point in the journal include:
• ALTER TABLE (especially REVALIDATE PRIMARY INDEX)
• RENAME TABLE
• MODIFY USER or MODIFY DATABASE
ARC is invoked by calling the program module ARCMAIN. You can run ARC on an IBM MVS or VM mainframe host or a Windows 2000 client. You also can run it in batch mode using BakBone NetVault with a Teradata application plugin.
Although ARC is most often invoked in batch mode using script files, it can be run interactively on an IBM host or Windows 2000 client. However, it does not provide a user-friendly interface for online sessions.
Archiving with NetVault
NetVault is a utility from BakBone Software, Inc., that provides a GUI front end and an ARC interface (via Teradata plugin modules) enabling you to back up and restore Teradata from an internal node or external machine. Two or more Teradata TPAs can be backed up by the same NetVault configuration.
Note: NetVault is a replacement for the Archival Storage Facility 2 (ASF2) and usually has been already configured, if needed, during your Teradata installation, upgrade, or migration. If you want to set up a new NetVault configuration, contact your NCR representative or the TSC.
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Teradata RDBMS Database AdministrationChapter 8: Archiving, Restoring and Recovering Data
Archive/Recovery (ARC) Utility
You create scripts to define the ARC ARCHIVE, COPY, and RESTORE commands, and execute those commands by running the scripts via the NetVault GUI. NetVault supports a variety of archiving options; for example:
• Selective backups, such as only the data dictionary (database DBC) tables, or permanent journals, or a single data table, and so forth
• Clustered node backups
• Restarting from a checkpoint
• Running multiple jobs in parallel
The NetVault solution for Teradata consists of the following:
Shared tape library A device that stores data on tape, including a robotic device that stores the tapes and is able to move them between the drives and the storage slots.
NetVault Domain A group of network-connected machines consisting of a NetVault Server, one or more NetVault Clients, and a tape drive and library.
NetVault Server software The controlling machine for a NetVault Domain. It adds and controls NetVault clients and devices, and holds the device and job definitions, schedules, and media and job information. A NetVault Server contains all the functionality of a NetVault Client and can act as a client to another NetVault Server. The standard installation includes an interface to control NetVault activities within the NetVault Domain.
NetVault Client software A machine with the NetVault software necessary to allow data to be archived or restored. Provided the NetVault Server is enabled for distributed device support (the usual case for Teradata operations), a NetVault Client can directly access the tape library device.
Teradata plugin software A value-added software module. The software for all Teradata plugins is identical; it functions as both the MASTER Teradata plugin as well as the Slave Teradata plugin.
MASTER Teradata plugin software Acts as an agent for the NetVault Server to control Teradata archive and recovery data flows. The machine selected as the master is knows as the MASTER Teradata plugin machine, whether NetVault Client or NetVault Server software is installed.
Slave Teradata plugin software Under control of the MASTER Teradata plugin machine, a Slave plugin is used to transfer data between the Teradata node and the tape library.
Backup system All TPA nodes installed with NetVault and connected to the tape device, and thus able to participate in NetVault ARC operations. The MASTER Teradata plugin must reside on one of these nodes. The NetVault Server machine can be one of the TPA nodes (internal), or a separate (external) machine. An external NetVault Server is recommended.