Ad loader does not over write the existing ETAs

On loading the ETAs into the DB, it doesn't overwrite the old ETA ads if any.
It doesn't affect the STAs as the contentElementTokenID for ETAs and STAs are different.
In production, this would not be a problem as ETAs will be loaded into DB for the 1st time.
But, in any case if you re-load the ETA file for a particular BA again, then there will be duplicates created. The work around is that before loading the ETAs for the 2nd time, you could delete the old ETAs manually and reload them.

QA4
SELECT * FROM content_repository.contentElementVariations WHERE contentGroupID IN (SELECT id FROM content_repository.contentGroups WHERE businessAreaID=10002)

has multiple entries of contentElementTokenID=17,18,19 from the previous load and the new load.