In the Analyzer page, you can select to create an new Analyzer or to use an existing Analyzer with the SQL statements that are already in the SQL Repository for that Analyzer.
Create a new Analyzer and select SQL to analyze
Specify to create an new Analyzer and to then select the SQL statements from the SQL Repository that you want to use in this new Analyzer.
Continue an existing Analyzer using the Analyzer's selected SQL
Specify to use an Analyzer that you have previously created with the SQL statements that are already stored with that Analyzer.
Analyzer Information
Item |
Description |
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Name |
If you are creating a new Analyzer, enter a name. If you are using an existing Analyzer, select the from the Select Analyzer box. |
Description |
If you are creating a new Analyzer, enter the description for the analysis. |
Last modified |
Displays the last modified date and time. |
Save location |
Displays the folder in the tree where the Analyzer is saved. In the bottom pane, select the folder where you want to save the Analyzer. To create a new folder, click . |
In the New Analysis wizard, the Select SQL page is used to select the SQL statements whose access plans you want to analyze in order to review the impact on their performance that the creation of new indexes would have.
The SQL statements used in an analysis can be taken from the SQL Repository or the SQL Scanner. If you select SQL statements from the SQL Scanner, these statements are added to the SQL Repository.
Select the SQL statements for the analysis. If you select SQL statements from the SQL Scanner, the bottom portion of this section displays the SQL Repository folder so that you can select the folder where they will be stored.
In order to analyze the impact the proposed indexes might have on the performance of the SQL statements, the Index Impact Analyzer compares the query before the indexes are created to the plans after the indexes are created. The access plans from before the analysis can be obtained two ways:
This option uses the access plan that was saved with the SQL statement when it was saved in the SQL Repository or SQL Scanner.
This option retrieves the access plan with the current logon and the current database settings. This current access plan is compared to the access plan that is retrieved after the new indexes are created.
In the New Analysis wizard, the Index page is used to specify the index(es) that are used for this analysis.
An individual Index Impact Analyzer consists of a group of stored SQL statements with the access plans called the " Baseline." The actual Impact Analysis is displayed in a "Scenario." A Scenario shows the comparison information for the stored SQL statements identifying the impact on the access plan that the creation of new index will have.
Item |
Description | ||||||||||||
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Name |
Enter a name for the Scenario. | ||||||||||||
Description |
Enter a description. | ||||||||||||
Add Index |
Click .
| ||||||||||||
Remove Index |
Click . |
After you have created the first Scenario, you can add more Scenarios.
The Add Index window is used to create the DDL for creating of the indexes for the Index Impact Analysis.
Item |
Description |
---|---|
Index name |
Enter a name for the index. By default, the prefix of the index name is taken from the Index Expert settings in the Options window and then a random number is generated for the rest of the index name. Note: It is best not to change the prefix for the index. The indexes are generated as virtual indexes. If the Impact Analysis process terminates abnormally and a virtual index is left on the database, it can be easily identified as a virtual index which was created by SQL Optimizer by the prefix. |
Database |
Select the database where the index is to be created from the database list. |
Owner |
Select the owner of the index from the drop-down list. |
Table |
Select the table where the index is to be created from the drop-down list. |
Table columns |
List of all the columns from the selected table. |
Index columns |
Move the columns to be indexed from the Table columns list by highlighting the column and clicking . |
Unique |
Specify to create a unique index. |
Clustered/Nonclustered |
Select to create either a clustered or a nonclustered index. |
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