Displaying Differences in Explain Text

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

Use Teradata Visual Explain to display the differences in the Explain text for two plans.

  1. Click . The Select Execution Plan(s) to Open window appears.

    Select Execution Plan(s) to Open

  2. From the Open Plans window, select one of the following options:
    • Plans from a database (go to step 3)
    • Open plans (go to step 4)
    • Offline plans (go to step 5)
    • DBQL plans (go to step 6)
  3. [Optional] To select plans from a database:
    1. In the tree view, right-click the Query Capture Databases node to open the shortcut menu.
    2. Select a specific QCD menu item to list the available QCD names in the tree view.
    3. Select a specific QCD from the QCD names in the tree view.
    4. Right-click the QCD name to open the shortcut menu.
    5. Select the Browse Plans menu item to display the Browse QCD Plans dialog box.
      To load … Do the following …
      Plans associated with a workload In the Workload box, enter the workload name or click to get a list of all available workloads.
      Specific plan Do one of the following:
      • Enter a query-tag name in the Query Tag box.
        In this field, the % and _ symbols can be used as wildcard characters and can be used in any combination. The % symbol represents any string of zero or more arbitrary characters. For example, query% would match query, query1, query12, and so on. The _ symbol represents one arbitrary character; therefore, any single character is acceptable in the position in which _ appears.
      • Type a query ID number in the Query ID box.
      Range of plans In the Query ID box, enter a range.

      For example, enter 1-100 or 1,3,6-10.

      Plans from a different server
      1. In the tree view, select Open Plan to open the shortcut menu then click the Connect menu item.
      2. After entering logon information, open the Browse Plans menu item for QCD,Browse DBQL Plans menu item for DBQL, and menu item Browse Offline Plans for Offline Plans.
  4. To select plans that are already opened:
    1. Select Opened Plan.
    2. Click Browse Open Plan(s). The plans are placed in the Available Execution Plans list.
  5. To select offline plans:
    1. In the tree view, right-click Offline plans to open the shortcut menu.
    2. Select the Browse Offline Plan menu item to display the Open dialog box.
    3. From the Open dialog box, choose one or more plans. When selecting a file, the description of the plan appears under Description. If the file contains more than one plan, the Description box includes the number of plans that the file contains.
    4. Click Open to place the plans in the Offline plans node in the tree view.
  6. To load one or more DBQL plans:
    1. In the tree view, right-click the DBQL XML plans to open the shortcut menu.
    2. Select the Browse DBQL Plans menu item to open the Select DBQL Criteria dialog box.
    3. Under Selection, use one of the following options:
      • Select DBQL (default) to browse XML queries from the DBQL.
      • Select External Database to browse XML queries from an external database.
    4. [Optional] Set other options in the Select DBQL Criteria dialog box and click OK. See Viewing the Execution Plan Graphically or Textually for more information about completing the Select DBQL Criteria dialog box.

      The filtered DBQL plans are populated below the DBQL XML Plan node in the tree view.

    5. In the list of plans in the tree view, right-click the QueryID and select Add menu item to enter a check mark in the QueryID check box.
    6. Enter data in the Select DBQL Criteria dialog box.
  7. [Optional] To see complete statement text, select a statement and then click .

    For more information on the Statement Text dialog box, see Viewing Statement Text.

  8. Select a base plan for the comparison by double-clicking a row in the Selected Execution Plans list. This moves the plan to the top of the Selected Execution Plans list and highlights the plan in green.
  9. Choose a plan to compare to the base plan by selecting the checkbox in the compare column next to the plan.
    Only two plans can be compared at a time.
  10. Click Compare.

    The compare window opens. The differences in the cells are highlighted in red.

    Compare Window

  11. Use the commands on the Navigate menu or the corresponding buttons on the toolbar to move from one difference to another.

    For more information about these commands, see Navigate Menu Commands and Toolbar.

  12. Click File > Close to close the compare window.