Blocking phantom reads/writes is usually only that of a serializeable transaction isolation level - and a range lock shouldnt block other writes, unless they ar

Blocking phantom reads/writes is usually only that of a serializeable transaction isolation level - and a range lock shouldnt block other writes, unless they are of the exact range specified, and then you are asking for a consistent view of reality. Generally I dont find adding more locks hurts things that are well designed - often you will find deadlocks turn into just waiting for your turn in line - and then you can tune your db code or your hardware or your whatever to maximize that throughput. Also fwiw if you are doing any sort of upsert and you are not locking for the update/insert combo, then you are definitely opening the door to a duplicate key insert - as long as you handle that though, nbd.