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Teradata RDBMS Database Administration - NCR

NCR Teradata RDBMS Database Administration - NCR , 2004. - 616 p.
Download (direct link): teradatadatabaseadmin2004.pdf
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"Building Baseline Transaction Profiles" using results derived from Teradata Performance Monitor and Resource Usage reports

For information on other query capture, resource management, and resource

monitoring tools, see:

Chapter 14: "Tracking Processing Behavior with the Database Query Log (DBQL)"

Chapter 15: "Tools for Managing Resources"

Appendix D: "Tools for Monitoring Performance"

13 - 2

Teradata RDBMS Database Administration Chapter 13: Database Analysis

Target Level Emulation (TLE)

Target Level Emulation (TLE)

Target Level Emulation (TLE) allows the TSC to emulate your production |

system for the purpose of query execution plan analysis. Query plans are generated on the test system as if the queries were submitted on the production system. The TLE achieves this by emulating the cost parameters and random AMP samples of your production system on the test system.

You use the Query Capture Facility (QFC) to capture the query execution plan.

You use the Teradata System Emulation Tool (TSET) to:

Export the information needed for emulation from your production system

Import that information on the test system

These features allow you to develop and analyze query plans without impacting your production system.

Caution: The TSC should run TLE on a test system; do not enable it on a production system.

For instructions and more information, see:

"Target Level Emulation" in Teradata RDBMS SQL Reference, Volume 2

Target Level Emulation field under "DBS Control Utility" in Teradata RDBMS Utilities

Teradata System Emulation Tool User Guide

Online help for Teradata System Emulation Tool

Teradata RDBMS Database Administration

13 - 3 Chapter 13: Database Analysis

Query Capture Facility (QCF)

Query Capture Facility (QCF)

The Query Capture Facility (QCF) allows you to capture the steps of the query execution plans. The query text and plans are stored in special relational tables that you create in a user-defined Query Capture database (QCD). The captured data is used to gather data demographics and analyze indexes for the tables referenced in the queries.

Note: You must upgrade a QCD that was created on a system earlier than V2R5.0. If the version of a legacy QCD is lower than QCF03.00.00, you also must migrate the data to a new QCD. Once upgraded, QCD can be utilized by the Teradata Index Wizard.

The source of the captured data is produced by the Teradata Optimizer, which outputs the text of SQL EXPLAIN detailing the final stage of optimization. (However, the current implementation of QCF does not represent all the information reported by EXPLAIN.)

The captured information is your workload, which becomes source input to:

The Teradata Visual Explain utility, which presents a graphical view of the flow of data during query execution. It also compares different EXPLAINs, either of the same query run on different Teradata configurations, or of semantically identical but syntactically different queries.

The Teradata Index Wizard, which recommends SI definitions that should improve the overall efficiency of the workload. Recommendations can include adding or deleting SIs to or from an existing design (see "Teradata Index Wizard" on page 13-10).

The following table summarizes the tasks you perform to establish a QCD and populate its tables.

IF you want to ... THEN . For instructions, see .
create a QCD Determine how much space you should allocate to the database "Sizing a Query Capture Database" in Teradata RDBMS Database Design
Use the Control Center feature of Teradata Virtual Explain to create the database Create a QCD from any database, including DBC, large enough to allocate enough space to hold the maximum expected output from DUMP/INSERT EXPLAIN. In Teradata RDBMS SQL Reference, Volume 2: - "Physical Limits for QCF" - "Setting Up QCD" Teradata Visual Explain User Guide

13 - 4

Teradata RDBMS Database Administration Chapter 13: Database Analysis

Query Capture Facility (QCF)

IF you want to

THEN

For instructions, see .

create the QCD tables

use one of the following:

Teradata Visual Explain utility. On a Windows 2000 server, the VECOMP.exe is located in:

drive:\Program Files\

NCR\Visual Explain x.x.x

BTEQ scripts containing the necessary CREATE TABLE statements

SystemFE.CreateQCFtable macro

In Teradata RDBMS SQL Reference, Volume 2:

- "Creating the QCD Tables"

- "Procedure Using the Visual Explain Utility"

Teradata Visual Explain User Guide

Basic Teradata Query Reference

SystemFE Macros

upgrade a legacy QCD and migrate the data to the new QCD

Use the Control Center feature of the Teradata Visual Explain Examine any applications written for the legacy QCD to see if it will work with the upgraded schema

"Compatibility Issues with Prior Teradata Releases" in Teradata RDBMS SQL Reference, Volume 2.

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