So it looks like there may be a linked article as it pertains to Incidents. I would do something like:
Update km_article
Set usr_incident = NULL
Where usr_incident != NULL
You have to clear all references before removing. The script you found is a basic script with the commonly removed items.
You will need to do more custom scripting to get out the information that it's telling you to remove. You have have to do a line of code per error received.