This can be achieved through an JDBC Event Enrichment policy, please follow these steps
1) Create a new event enrichment policy
4) Deploy this policy to MTC or individual connector like Universal or Spectrum etc
5) Modify the policy file with below SQL query in \SOI\resources\Core\Catalogpolicy\extensions and save the file
query="select UserDefinedCol1 from CI where DeviceID in (select DeviceID from CIStaging where CINamespaceMapID=?) and CI.UserDefinedCol1 is not NULL"
6) The ‘CI User Attribute’ is available to the CI that is modeled
1) First, add a value to ‘CI User Attribute (1)’ for the ComputerSystem CI as shown in the picture
7) When an alert generated on any of the child CIs, the Event Enrichment DB policy will run the SQL query to get User Attribute value against ‘CINamespaceMapID’ and update alert “User Attribute” property. As you see in the below screenshot, there are alerts on child CIs like Processor, Memory etc and the UserAttribute10 is updated with a value of Parent CI "CI UserAttribute1"