How does discovery model verify if its a duplicate before creation? - Support and Troubleshooting

How does discovery model verify if its a duplicate before creation? Issue  Overview The discovery model is created by a business rule "Create a Software Normalization". This rule checks for the primary key data before it creates a discovery model. If the primary key of the record matched the primary key of the discovery model then it will update the matched record else it will create a new discovery model.

Business rule that creates discovery model: https:// .service-now.com/sys_script.do?sys_id=9ec2b34d37101000deeabfc8bcbe5d43&sysparm_view=&sysparm_record_target=&sysparm_record_row=1&sysparm_record_list=nameCONTAINScreate+a+software%5EORDERBYname&sysparm_record_rows=2

The primary key field is a value that is built based on the serial number and other factors. The business rule that builds the primary key is as below.

https:// .service-now.com/nav_to.do?uri=%2Fsys_script.do%3Fsys_id%3Defd6bb4d37101000deeabfc8bcbe5d44%26sysparm_record_target%3Dsys_script%26sysparm_record_row%3D3%26sysparm_record_rows%3D15%26sysparm_record_list%3DnameCONTAINSprimary%255EORDERBYname