Audit Trail

An audit trail is the memory a system keeps of itself, a plain record of who did what and when. Every time somebody changes a price, cancels an invoice, corrects a phone number or opens a patient file, one line is written in a place the daily screens never show. That line carries the name, the date, the time and usually the value before and after the change, which is what makes it worth keeping.

Most people meet the idea during an argument, when a customer swears the invoice was cancelled by mistake or an accountant is certain the discount was never approved. With no record the loudest voice wins, and with one the question takes two minutes and nobody is blamed for something they did not do. The record only works, though, if the system stops throwing things away.

A careful system therefore never truly deletes anything. The row is marked as removed and disappears from the list, yet it stays in the database with the name of whoever removed it. Staff often ask us to make delete mean delete, and we say no for one reason. The week money goes missing is the week you need the rows somebody deleted.

Reading is part of the trail too, and that is the part people forget. In a clinic, who opened a file matters as much as who edited it, so Linkysoft records a viewed patient history exactly like an edit. Staff curiosity is a genuine risk, and honest people are usually glad of a record that proves they were nowhere near a file. The habit comes from our cybersecurity work, and it is built into DocMz, our hospital and clinic system.

Two questions are worth asking a supplier before you sign, and the first is how many years the history is kept. The second is whether anyone holding an administrator password can erase it, because a trail a manager can quietly wipe is not a trail at all. It should sit apart from the daily data, out of reach of the people it describes.

All of this costs something, since the tables grow and a busy shop can write more history lines than sale lines. Storage is cheap next to a single disputed refund, so Linkysoft switches the trail on by default in every web application we build. We then agree with the owner how long each kind of record should be kept.