Auditing past trade adjustments
In Late trade adjustments we saw the ability to make changes to the previous day’s records.
Let’s say instead of backfilling a trade to the previous day, someone adds a trade a month ago.
Now when the auditors come in, they check for changes since they last were here:
They can’t find the trade we inserted into last month!
If we want to allow editing the timeline, how can we detect this?
In XTDB we use system-time (a.k.a. wall-clock time), an immutable timeline that gets appended to with every change. This means our fraudulent/malicious/accidental edit from earlier gets caught easily:
In fact we can even scan the system for suspicious or unusual changes. For example, any retroactive changes to valid-time that go back further than 24 hours:
Conclusion: As an immutable database, XTDB keeps you safe from your own changes by making sure to record when they happened. Even when reaching into the past!