Edited; removed FGDB-specifics in title since I already have an idea for that.
In the Attribute Table:
Could a could button be added for selecting rows where a specified field has duplicates? For example, select rows where the ASSET_ID field is duplicated.
It would be similar to the functionality this SQL expression provides, except this expression doesn't work for file geodatabases: ERROR 000358: Invalid expression:
asset_id in (select asset_id from sidewalks group by asset_id having count(*) > 1)
Due to that FGDB SQL limitation, I imagine the functionality would need to be ArcObjects behind the scenes, not SQL.
I'm aware of the Find Identical tool. That tool exports a new dataset. I want to dynamically select in my existing dataset.
Related: Select By Attributes — Select Duplicates