If you want to have integrity control, you can use digital signatures without blockchain.
If all you're trying to fix is making it hard to issue a DELETE statement, then make it easier to set permissions. Which isn't really hard in any mainstream database...
It seems like this is a log, which might work better, although existing RDBMS already have high performance versioning/change tracking.
Of course you can use signatures as you basically start recreating blockchain at that point (eg, each transaction is signed and linked to the previous; then connected with other nodes doing the same thing. A change to any segment would be detectable, etc etc).
Basically, it is just a distributed log that removes any change for changing data and the inability to set any permissions to remove data.
Maybe I’m being dense, but please let me know of any mainstream databases that give this functionality without relying on permissions to insure integrity. If an admin is able to change data, then that won’t work in my use case.
You can copy it, filter-branch it. But if something is deleted the hash will be different.