The results from the Run for All Records, the Run for First Record, and the Batch Run are placed in the bottom Pane of the SQL Optimizer window for you to analyze and pick the SQL statement that is the best performing in your database environment. These results are displayed in the Time, Statistics, and Charts tab.
The Optimization process numbers the SQL alternatives according to the Estimated I/O cost.
This is a cost estimation calculated by Adaptive Server. It is only an estimation and should not be used to determine the best performing SQL.
This shows the SQL statements that have abstract plans that are compatible with the original SQL statement.
The execution time (in clock time) that it takes the SQL statement to select all records or the first record. This figure may include time that Adaptive Server spent on processing other tasks or waiting for disk or network I/O to complete. This is the accumulative run time for the SQL statement. The individual values for the Elapsed Time can be view by clicking All Records or First Record on the top right pane of the SQL Optimizer window.
If the original SQL statement run time is available, the Times of Improvement indicates how much faster the alternative SQL is than the original SQL.
The CPU Time is accumulative total for the CPU time to execute the SQL statement. The individual values for the CPU time can be view by clicking All Records or First Record on the top right pane of the SQL Optimizer window.
The Actual I/O Cost is a calculation from Adapter Server after the SQL statement is executed in the Batch Run or the Run Time function.
The Records column shows the number of records processed by the SQL statement. This number should be constant. It is an indication that the alternative SQL statements are semantically equivalent to the original SQL statement.
Information from the Batch Run is included in this column. It includes:
If the SQL was terminated by the termination criteria.
If the SQL was run more than once.
If a database error occurred.
Note: Estimated I/O cost, All Records Actual I/O Cost and First Record Actual I/O Cost are not available for logon users without sa_role privileges or with the "allow resource limits" configuration parameter turned off for the Adaptive Server. To retrieve the Estimated I/O Cost, All Records Actual I/O Cost, and First Record Actual I/O Cost estimations, you should either grant yourself sa_role, logon as another user with sa_role privileges, or turn on the "allow resource limits" parameter:
sp_configure "allow resource limits", 1
The Statistics tab of the Run Time pane in the SQL Optimizer window shows the statistics the accumulative totals for the CPU Time, Scan Count, Logical Reads, Physical Reads, and APF I/Os from the execution of the SQL statement. To see the individual values for the statistics by table, click All Records or First Record on the top right pane or the Statistics tab at the bottom of the SQL Optimizer window.
For more information about this statistics see the Adaptive Server Performance Tuning: Monitor and Analyzing manual, Chapter 4.
Charts are available for all the statistics and run times. Three chart panes display the run time information.
To change the information in the chart
Click the Chart Title and select the following functionality:
A performance forecast based on the retrieved Estimated I/O Cost value. If the Performance Projection value is greater then one, then it is forecasted that the SQL alternative may give a better performance.
Charts the estimated I/0 cost from the SQL statement with the corresponding indexes.
Charts the following statistics for All Records or First Record after the run time is retrieved for a SQL statement using the Batch Run, Run for All Records, or Run for First Record.
Statistics | Description |
Elapsed Time | Charts the execution time (in clock time) that it takes the SQL statement to select all records or the first record. This figure may include time that Adaptive Server spent on processing other tasks or waiting for disk or network I/O to complete. |
Times of Improvement |
How many times faster the alternative SQL statement is compared to the original SQL. |
CPU Time |
Charts the execution time (in CPU time) that it takes the SQL statement to select all records or the first record. |
Actual I/O Cost |
Charts the Actual I/O Cost of executing the SQL statement from Adaptive Server. |
Elapsed Time + CPU Time |
Charts side by side the Elapsed Time and the CPU Time. |
Writes |
Charts the accumulative number of disks writes for the SQL statement run time statistics. |
Scan Count |
Charts the accumulative number of scans for the SQL statement from the run time statistics. |
Logical Read |
Charts the accumulative number of logical reads for the SQL statement from the run time statistics. |
Physical Read |
Charts the accumulative number of physical reads for the SQL statement from the run time statistics. |
Apf IOs used |
Charts the accumulative number of Apf IOs for the SQL statement from the run time statistics. |
Charts the following statistics.
Statistics |
Description |
All Records | Charts the Elapsed Time + CPU Time, Actual I/O Cost, and Times of Improvement for all records. |
First Records |
Charts the Elapsed Time + CPU Time, Actual I/O Cost, and Times of Improvement for the first record. |
All Records vs. First Record |
Charts the Elapsed Time for all records and the first record. |
All Records vs. First Record with Cost |
Charts the Estimated I/O Cost, the Elapsed Time + CPU Time (for all records), and Elapsed Time + CPU Time (for the first record). |
Print the chart.
Save the selected chart.
Hide the selected chart.
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