On the face of it, who cares if the public knows your name and what office you work in, but for PSNI officers this kind of information could have catastrophic consequences.
Police officers in Northern Ireland go to great lengths to keep their private information under wraps.
For many officers they have only told their closest family what their job is, keeping that secret from the wider circle.
Often when asked where they work they simply say civil servant, not inaccurate but not completely truthful.
PSNI officers live under constant threat from dissident republicans who want to kill them.
Every member of the force is issued with a personal protection weapon which they carry on duty, but such is the threat against them that they carry that weapon off duty as well.
Just a few months ago Detective Chief Inspector John Caldwell was shot multiple times while he was coaching a youth football team in Omagh.
This data breach poses a security threat for officers on a scale they would never have imagined possible.
It exposes them firstly as police officers and secondly gives valuable information as to what they do within the PSNI.
We now know there are 40 officers who are assigned to work with MI5 on national security issues.
That is likely a secret those officers would have kept from even those who knew they were police officers.
Does that now mean covert operations have been compromised as a result?
Officers are regularly told to change the route they take to work to avoid ambush, what is the point of that if those intent on killing an officer now know exactly which police station they are driving too.
Northern Ireland is large enough that if an officer is no longer able to work in an area due to a death threat they can be moved to another area, essentially disappearing from their original station.
Those dissident republicans will still have a target on that officer's back, but will not know where they have gone to.
If this data gets into the wrong hands the work to move those officers will have been undone.
Fines for the data breach and compensation could reach £20million.
Some officers may have to move home as it becomes obvious the general area they are living in.
Roles may have to be changed and personnel moved around the organisation.
The final cost of this is hard to work out.
Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To Know.