Is there any code available to deallocate IP address assigned by VRA in a network profile
This is one of the possible way, please check this and see if that helps:
https://open902.com/vrealize-automation-7-2-make-ip-in-network-profile-unavailable-for-deployments/
regards
Gayathri
Directly modifying the SQL IaaS database is not only unsupported but could break a lot of things. One should never resort to such things in an attempt to cobble their own home-grown solution together. You could put yourself in real trouble if you do.