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Introduction to the Teradata® RDBMS for UNIX® Version 2 Release 2.1 - NCR

NCR Introduction to the Teradata® RDBMS for UNIX® Version 2 Release 2.1 - NCR, 1998. - 315 p.
Download (direct link): inntroduktionteradata1998.pdf
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Account String Expansion

Substitution Variables for ASE


Account Usage

Most account usage information is best gathered by the client system.

You can use client-provided facilities to gather information about RDBMS use by accounts by recording logon/logoff activity.

You can also use client-provided solutions to capture attempted security violations.

The principal Teradata RDBMS feature for accounting is the optional Account String Expansion (ASE) capability.

ASE permits you to use substitution variables to include date and time information in the account ID portion of a user logon string. The system inserts actual values for the variables at Teradata SQL execution time.

ASE permits more accurate measurement of individual Teradata SQL statement execution, more precise statistics, more accurate capacity planning, and more information for chargeback and accounting software.

The following table describes the substitution variables for ASE.

Substitution Variable Description Format
&H Hour HH
&L Logon timestamp YYMMDDHHMMSS.hh

An example of how to use the ASE substitution variables might be the following, where the ASE variables are appended to a typical BTEQ logon string:


At Teradata SQL execution time, the system replaces &D with the current date and replaces &T with the current time.

For each account string in effect, the system collects and stores a set of statistics as a row in the Data Dictionary in a table called DBC.AMPUsage.

Introduction to the Teradata RDBMS for UNIX

System Administration

Account Usage

Account Performance Groups

ASE can generate a summary row for each of the following:

• Teradata SQL request

• User

• Session

• Aggregation of daily activity for a user

You can specify collection rates for statistics based on the date and time of the request or by the time the user logs on.

Performance groups are a mechanism to allow system resources to be distributed among sessions predictably.

When an account id prefixed with a group code is provided in a LOGON string, the session is assigned to the associated performance group when the logon is successful.

If this form of account id is not present, the session is assigned a default value corresponding to the group specified by $M.

Each session is assigned, either explicitly or implicitly, to a performance group, and each performance group is assigned a proportional resource weight.

The Fair Share Scheduler manages the workload based on the relative priority of each group’s resource weight.

This weight does not guarantee system responsiveness in a corresponding proportion because responsiveness is a function of overall system activity.

Codes and their associated group names are listed in the following table.

Code Performance Group Description of Resources Allocated
$L Low Half the computed resource allocated to a $M session.
$M Medium Default.
$H High Twice the computed resource allocated to a $M session.
$R Rush Four times the computed resource allocated to a $M session. Should be used only for administrative and supervisory users.


Introduction to the Teradata RDBMS for UNIX
System Administration



Teradata Manager


This topic discusses how the Teradata RDBMS monitors aspects of the system such as:

• System states

• Resource usage

• Performance

The Teradata Manager is a production and performance monitoring system used to monitor, control, and administer one of more Teradata servers.

The Teradata Manager provides a variety of tools and applications to gather, manipulate, and analyze information about the RDBMS on which you are working.

From a single platform, you can query, manipulate, and analyze the information your need.

Introduction to the Teradata RDBMS for UNIX

System Administration

System and Configuration Status

System and Configuration Status

The Teradata RDBMS is always defined to be in one of several potential states. You can monitor these states from the Database Window. The following table lists and describes the states.

Status Description
Offline Either the processor to which the RDBMS console is attached or the entire RDBMS has been started offline. The RDBMS cannot be accessed from a client or used for processing.
Startup The system is starting up but is not ready to process requests.
Logoff No new sessions may log on (logons are disabled), but one or more sessions remain logged on.
Logoff/Quiet No new sessions may log on and no sessions are logged on. The system is quiescent.
Logon New sessions may log on (logons are enabled) and one or more sessions are logged on.
Logon/Quiet New sessions may log on (logons are enabled), but no sessions are logged on.
Reconfig The reconfiguration program is running.


Introduction to the Teradata RDBMS for UNIX
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