Viewing Comparison Reports

Teradata Visual Explain User Guide

brand
Teradata Tools and Utilities
prodname
Visual Explain
vrm_release
16.10
16.20
category
User Guide
featnum
B035-2504-086K

This chapter explains how to view comparison reports and provides information about the reports. For more information, see:

Use Teradata Visual Explain to compare the execution plans across different QCDs or across different Teradata Database systems. Teradata Visual Explain creates a number of reports comparing various attributes of the plans. These reports help identify the differences in the plans. Attributes with differences are highlighted in the report.

The following two methods are used for comparing reports:
  • Method 1: Compare the response time or join plans of queries in the following circumstances:
    • On systems with different configurations
    • Across two different Teradata Database releases
    • With changing demographics
    • By adding an index and dropping an existing index
  • Method 2: Compare reports of two plans using either of the following:
    • An online comparison of any two plans opened in the Teradata Visual Explain interface.

      To learn how to select plans for textual comparison, see Comparing Execution Plans Textually.

    • The comparison reports of a previous bulk compare operation.

      To generate the comparison, double-click a cell in the Bulk Compare report viewer.

Each report provides information on the base query and current query.

A base query is the query against which the current query is compared:

  • If the report is opened through online comparison of plans, the base query is the one that is selected in the first row under Selected Execution Plans.

    For more information on selecting a base query, see Comparing Execution Plans Textually.

  • If the report is opened through the Bulk Compare report viewer, the base query is available in the first column.

The current query is the query selected for comparison against the base query.

  • If the report is opened through online comparison of plans, the current query is the one that is selected in a row other than the base query under Selected Execution Plans.

    For more information on selecting a current (or compare) query, see Comparing Execution Plans Textually.

  • If the report is opened through the Bulk Compare report viewer, the current query is available in the cell that is double-clicked.