To show or hide a column attribute
Select the Schema Information tab in the Optimize SQL window.
Click besides the Summary list and select a table.
Right-click the header row of the Column Attributes pane and select Column Chooser.
Note: The Column Attributes pane is the second pane in the Schema Information tab.
Add or remove column attributes by dragging the column names to and from the Customization dialog.
Use the Compare window to view the SQL text, execution plan, and execution statistics for your original SQL statement and all alternatives SQL Optimizer generated. The Compare window consists of the Alternatives window and the Comparison window. The Alternatives window displays execution statistics and the Comparison window displays SQL statements and execution plans. You can compare your original SQL statement with an alternative SQL Optimizer generated or compare two different alternatives.
Note: This topic focuses on information that may be unfamiliar to you. It does not include all step and field descriptions.
To compare SQL statements
Select an alternative in the Alternatives window to compare the statement with your original SQL statement.
Note: The Comparison window displays the SQL text and execution plan for the original SQL statement in both panes by default.
Tip: The alternative you selected is shown under your original SQL statement in the Alternatives window by default. To unfreeze the alternative selected, right-click the alternative and select Unfreeze Comparing Rows.
Click to switch the location of the original SQL statement and selected alternative in the Comparison window.
Note: Change the location of the original SQL statement to compare two alternative statements. Once you select the first alternative, click and select the second alternative.
Click the current layout option in the Comparison Window to change the layout for the statements you are comparing. Review the following for additional information:
|SQL and Plan (Left-Right)||Displays the SQL text and execution plan for the statements you are comparing side by side.|
|SQL Only (Left-Right)||Displays the SQL text for the statements you are comparing side by side.|
|Plan Only (Left-Right)||Displays the execution plan for the statements you are comparing side by side.|
|SQL and Plan (Top-Bottom)||Displays the SQL text and execution plan for the statements you are comparing beneath each other.|
|SQL Only (Top-Bottom)||Displays the SQL text for the statements you are comparing beneath each other.|
|Plan Only (Top-Bottom)||Displays the execution plan for the statements you are comparing beneath each other.|
You can generate a resolution report in SQL Optimizer after you optimize your SQL statement and execute the alternatives. The resolution report includes the following:
Original SQL statement
Optimization Session Information
Best Alternative Scenario
To generate an Optimize SQL resolution report
Click in the Report window to customize the information displayed in the resolution report.
Tip: You can display execution plans in text mode, grayscale graphic mode, or full color graphic mode.
After you optimize the original SQL statement and determine the best alternatives, you may find the performance of the selected statements unsatisfactory in your database environment.
To remedy this, check if SQL Optimizer reached any of the optimization quotas for your original SQL statement. Select SQL Information in the Execution Plan pane and select Alert to view this information. Make adjustments to the intelligence, optimization, hints, or quota setting options if SQL Optimizer has reached any of the quotas. To access these settings, click and select Optimize SQL.
Additionally, review the execution plan of the original and optimized SQL statements to check if you need to change the database structure.