Data Model Name Child Objects Property Values
Final output required as through search query not in data model record1
| set union [| datamodel search | fields + "field1" "field2"] [| datamodel search | fields + "field1" "field2"]
Above solution is verified and working.
Try this instead http://answers.splunk.com/answers/215346/best-practices-to-join-two-child-objects-of-a-data.html , it will be much faster