Back wne I was at Uni, in the 80s, we looked at database theory. Standard technique for indexed sequential databases where you really don't want to fragment the file: when you "delete" a record, you don't remove it, you merely set a flag. When a new record is created, if a flagged record is of equal or slightly greater size you overwrite it.
Every so often, you vaccuum the database to eliminate gaps and remove any flagged records still left.
This gives you a situation where a record is not deleted immediately but is deleted when performing a different operation (an insert or a vaccuum).
This was considered a fairly basic, crude system that was a holdover from sequential media like magnetic tape.
This system would infringe the patent, despite the fact that I seriously doubt anyone has used magnetic tape for live database work within the lifetime of anyone involved in writing said patent or enforcing it in court.
The part that makes me concerned, though, is that this caswe is giving the impression to other companies that patent trolling is easy money and that actual software development is high-risk. That's an extremely dangerous mindset. When you start believing that producing is bad and privateering is good (privateering is piracy in the cutlass-and-walk-the-plank sense that has been legalized by a government), what do you imagine happens?