The submit-based approach employs the Optimizer to determine if a statistic needs to be collected. You can enable collect thresholds to prevent repeat collection of statistics that were recently collected or have not changed significantly.
Following is an overview of the tasks employed in this approach:
- Change the Collect age threshold and Data change threshold on the Edit Collect Settings dialog box to skip the collection of statistics that were recently collected or have not changed significantly.
- Run the collect jobs frequently.
When a job is run, the Optimizer determines which statistics to collect, based on the threshold settings.
Review the Collect Job report for a list of collected and skipped statistics.
- Verify that all the automated statistics are submitted for collection.In the Statistics by Database view, examine the Max Submit Age metric for databases or Submit Age metric for objects. If the value is greater than the expected frequency, check the following:
- Statistics are associated with a collect job
- Collect job is scheduled to run with the expected frequency
- End state of the collect job is Complete or Partially Complete.
If the job is Partially Complete and not scheduled to resume, the job duration may be too short.