There may come the need for a Performance Analytics Administrator to clear or purge the data from certain tables in the Performance Analytics system.
This article will describe and detail some of the methods that can be used to clear such data. Caution should be exercised of course, as these deletions are irreversible operations.
As mentioned above, there are a few methods in which this can be done. The first method is the method that can be used for removing data as associated to a specific Indicator and also any Breakdowns associated to that Indicator. This method is not necessarily recommended for deleting data for many indicators, as there are other methods which can be used to delete data on a larger scale which do not require as much intervention from the end user. To thus delete this data from a specific Indicator and also potentially as associated to the Breakdown Elements, follow these steps:
Log into the instance with an account having the admin or pa_admin role on the instance.
Using the Menu Navigator, browse to the following location: Performance Analytics -> Scoresheet.
From the pulldown list at the top of the screen, select the name of the Indicator for which you want to remove all collected data. The scoresheet should then display with the applicable scores.
Click the Delete all scores button found in the upper right corner of the scoresheet display.
A dialog box will appear with a message indicating that all scores associated to this indicator will be deleted from the instance and requesting you to confirm that these records should be deleted. If you are sure you want to delete these scores, click the OK link on the dialog box.
Clicking OK will then delete all scores associated to that Indicator and reload the form, showing no scores in the scoresheet. Clicking Cancel will return the view to the scoresheet display with no deletions having taken place.
Note that this deletion includes not only the most recently collected scores, but also all historical scores associated to this Indicator as well.
A more global deletion can also be performed, in which all performance analytics scores on the entire system can be deleted. As this will essentially reset all the Performance Analytics data on the entire system this should be done with extreme caution. Essentially, this step will consist of mass deleting all the scores from the applicable Performance Analytics score tables in the instance. This could also be done using a Background Script or using the steps as outlined above for each Scoresheet that contains scores on the system. Thus, perform these steps to delete all the Performance Analytics scores on the instance:
Log in to the instance with an account having admin rights to the instance.Using the Menu Navigator, browse to the following location on the instance: System Definition -> Tables. A list of tables will appear. Locate the table in the list with a name of pa_scores_l1 and a label showing Score Level 1 and click the Information icon to the right of that record to open the record.
Click the Delete All Records button that appears in the upper right corner of the table record.
A confirmation box will appear prompting the user to type the word "delete" in the text field. If you are absolutely certain you want to delete all the records in this table, type the word delete in the field and click the OK button. If you decide not to delete the records, click the Cancel button which will cause no records to be deleted from the table.
If you confirm you want to delete all the records in the table, the screen will return to the table record and after a few minutes a dialog box should appear indicating that some number of records has been deleted from the table. Note that if there are a large number of records in this table, the delete operation could take several minutes or more.
Click the Close button to close the confirmation dialog box and return to the table record.
Click the Back icon at the top of the record to return to the list of table records.
Repeat these same procedures for the following additional tables in this list:
Note that the table with the name "pa_scores" may not contain any data in versions of ServiceNow which were originally assigned in versions after the Istanbul version.
After performing these steps, all the Performance Analytics related score records will have been removed from the instance. As such, any Dashboards, reports or other objects that rely on these values will show empty counts. Thus, after performing these steps you will probably want to begin recollecting the applicable data through daily or historical Performance Analytics jobs.
Automatic Deletion of Performance Analytics Data
It should also be noted that the system is configured with a special Scheduled Job that automatically deletes old Performance Analytics score data from the applicable tables. This Job is called Clean PA collections and is pre-configured to run once every day. This job will delete all scores older than the instance configured number of days which is specified in the System Properties com.snc.pa.dc.keep_scores_for.frequency and com.snc.pa.dc.keep_snapshots_for.frequency.
For additional information regarding configuring the PA Score collection cleanup job, including modification of the length of time to retain these records for or the time each day you want to have this score cleaner run, see the following KB article: