Textual Comparison
Use Teradata Visual Explain to generate a textual comparison of execution plans using reports.
To compare execution plans textually
1 Click .
The Select Execution Plans for Textual Compare dialog box appears. The following selections are available:
2 [Optional] To select plans from a database, use one of the following options:
To Load ... |
Do the following … |
The plans associated with a workload |
In the Workload box, enter the workload name or click to get a list of available workloads. |
A specific plan |
In the Query Tag box, enter the name of the query tag. [Optional] In this field, the percent sign (%) and underscore (_) can be used as wildcard characters and can be used in any combination. The percent sign (%) represents any string of zero or more arbitrary characters. For example, query% would match query, query1, query12, and so on. The _ represents one arbitrary character; therefore, any single character is acceptable in the position in which the underscore character appears. – or – Enter one query ID number in the Query ID box. |
A 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 |
In the tree view, select Open Plan to open the shortcut menu. Click the Connect menu item. 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. |
View XML plans |
Select QCD XML Plans. |
3 To select plans that are already open:
a Click Browse Opened Plans.
b Click Open to display the plans.
The plans are listed under Selected Execution Plans.
4 To select offline plans:
a Click Offline Plan in the tree view, and select Browse Offline Plans.
b 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 identifies the number of plans the file contains.
c Click Open. The plans are displayed in the Offline Plans node.
5 [Optional] To load one or more DBQL plans:
a In the tree view, right-click on DBQL XML Plans to open the shortcut menu.
Select the Browse DBQL Plans menu item to display the Select DBQL Criteria dialog box.
b Under Selection, use one of the following options:
c [Optional] Set DBQL filter options:
i DBQL Filter Options are present in the Select DBQL Criteria dialog box.
i DBQL Filter Options are present in the Select DBQL Criteria dialog box.ii Click OK.
d Filtered DBQL plans populate the tree view under the DBQL XML Plan node.
e In the Available Execution Plans, right-click on the QueryID to open the shortcut menu and select the Add menu-item checkbox in the Available Execution Plans list.
f To select a base plan for the comparison, double-click on a row under Selected Execution Plan.
6 [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” on page 83.
7 Select a base plan for the comparison by double-clicking on a row in the Selected Execution Plans list. This moves the plan to the top of the Selected Execution Plans list and the plan is highlighted in green.
8 Choose a plan to compare to the base plan by selecting the checkbox in the compare column next to the plan.
Note: Only two plans can be compared at a time.
9 Click Compare to display the reports. The differences in the cells are highlighted in red.
To view comparison reports, see “Chapter 10 Viewing Comparison Reports”
To print a textual compare report, see “Printing Textual‑Compare Reports” on page 142.