You need to define the values of SQL statement variables before you optimize the statement. The Set Bind Variables window displays automatically when you use SQL Optimizer for a statement with variables.
Troubleshooting: If the Set Bind Variables window displays when you optimize a statement without variables, make sure you spelled the column and table names correctly, you selected the correct database or user, and you selected a table or column that exists in the database.
Note: This topic focuses on information that may be unfamiliar to you. It does not include all step and field descriptions.
To set a bind variable
Enter a SQL statement with a bind variable.
Note: SQL Optimizer currently supports the following bind variables data type:
CHAR
Click .
Review the following for additional information:
Bind Variables List | Description |
Datatype |
Click |
Null |
Select the checkbox if the value for the variable is null. |
Variable Value |
Enter a value for the variable. |
Browse Data | Description |
SELECT |
Click Note: SQL Optimizer selects the All Columns checkbox by default. |
FROM |
Click Tip: Click |
WHERE |
Enter a WHERE clause or click |
ORDER BY |
Enter a ORDER BY clause or click |
Use the Alternatives pane to review the SQL text and execution plan for the alternatives SQL Optimizer generates. You can also review the run-time statistics for your original SQL statement and the alternatives after you execute the statements.
Note: This topic focuses on information that may be unfamiliar to you. It does not include all step and field descriptions.
To review details for an alternative
Select an alternative in the Alternatives pane.
Review details for the alternative in the Alternative Details and Execution Plan panes.
Automatically Optimize SQL Statements
Status | Displays client status. |
Status | Displays client status. |
Elapsed Time | Displays the execution time to retrieve the entire result set. |
SQL Information | Description |
SQL name |
Name of the SQL statement. |
Classification |
Statement type as classified by SQL Optimizer. Types include Simple, Complex, or Problematic. |
Classification Rules Detail | Description |
Details |
Applicable SQL Classification Rules. Rules used for the classification process are set in the SQL Classification Options menu. |
Note:SQL Classification information only displays for the original SQL statement. |
The text editor is used to display the SQL text of the selected alternative. When there’s only original alternative or the selected alternative is user defined, the SQL text can be edited. Otherwise, it’s read-only.
Note: This topic focuses on information that may be unfamiliar to you. It does not include all step and field descriptions.
To view optimization details
Select the SQL Information tab in the Optimize SQL window. Review the following for additional information:
Optimization Details | Description |
Intelligence level |
Intelligence level used for optimization. This option is set on the Optimizer Intelligence options page. Intelligence Options |
Semantically equivalent SQL statements |
Number of semantically equivalent SQL statements generated by SQL Optimizer. |
Alternative execution plans produced |
Number of alternative execution plans produced for the original SQL statement. |
SQL statements eliminated due to identical execution plans |
Number of statement alternatives eliminated with the same execution plan as the original SQL statement. Note: SQL statements with the same execution plan produce the same run time because the database executes these statements in the same way. Therefore, SQL Optimizer eliminates alternatives with equivalent execution plans. |
Optimization Time Details | Description |
Optimization started at |
Time optimization started. |
Optimization finished at |
Time optimization finished. |
Total optimization time |
Total time to complete optimization. |
Average optimization time |
Average time to generate each statement alternative. |
Notes:
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