Delete Data Infinite Loop

This Knowledgebase article applies to:

• SigQC version(s) 2.02.02 on the following platforms: All Supported

Symptoms:

When deleting data using the Edit | Delete Data menu, the status bar continues to show good progress, but the process never stops. This process can be a very long process, but anything over 10 hours is probably a good indication that you have this problem.

Cause:

The problem occurs when you try to delete all the data (i.e. all data before today’s date). SigQC/PTA deletes data sets in groups of 10,000 records. For this deletion case, the code was written to get the oldest 10,000 records, check that they were not part of the Target Data Pool, and delete the ones that were not.

It repeats this process until all non Target Data Pool data is deleted. If there are over 10,000 records in this database which are in the Target Data Pool than this code generates an infinite loop. The problem is that the code gets the oldest 10,000 records (which in this case are all part of a Target Data Pool), tries to delete them (but none delete since they are all in a Target Data Pool), loops around and gets the
oldest 10,000 records (which are the same records from the previous loop) and therefore never makes any real progress in the deletion of data.

Resolution:

There is a work around until the code is fixed.
If when specifying the data to delete you were to use the case of Delete Data Between two dates, you could pick your dates to avoid including the 10,000 or so Target Data Pool data sets.