15.00 - Cost Parameters - System Emulation Tool

Teradata System Emulation Tool User Guide

prodname
System Emulation Tool
vrm_release
15.00
category
User Guide
featnum
B035-2492-034K

Cost Parameters

Select the Cost Parameters check box to export the Optimizer environmental cost parameters and DBS Control information from a target system. Cost parameters are captured from the system Globally Distributed Object.

To change the cost parameters export options

1 From an export dialog box, click Options.

The Export Options dialog box appears.

2 [Optional] In the Cost tag box, type a new file name.

By default, the Cost tag box displays the file name entered when choosing an export method in the Export from Teradata Database dialog box.

3 To capture cost data from specific rows, click Select Rows.

The Export Cost Parameters dialog box appears.

4 Select a method for exporting cost parameters.

 

Option

Description

Capture from Source

Export cost parameters from SystemFE.Opt_Cost_Table for the selected rows.

Cost parameters and related DBS Control information is exported after parameters are captured from the target system.

Capture Current Costs

Export the cost parameters and DBS Control information from the target system.

A row is inserted into SystemFE.Opt_Cost_Table and SystemFe.Opt_DBSCtl_Table using the cost tag specified in the Cost tag column. The row is exported and then deleted from SystemFE.Opt_Cost_Table and SystemFe.Opt_DBSCtl_Table after the export process is complete.

Set Costs

Set and then export the cost parameters for a given row.

This option is available only when an entry exists in SystemFE.Opt_Cost_Table. Only one cost parameter can be set for a system. It ensures that the Optimizer ignores the current system parameters and uses the new parameters when generating an execution plan. Using this option is similar to using a DIAGNOSTIC SET COST statement.

Note: This option is available only when exporting by query. TLE must be turned on before setting cost parameters. Be aware that TLE might cause system performance degradation. For more information about TLE, refer to SQL Request and Transaction Processing B035-1142.

5 Click OK to close the Export Cost Parameters dialog box and return to the Export Options dialog box.

6 Click OK to close the Export Options dialog box.