Reference Field Selection - Concurrent Users

[Jags5]

I have a reference field (device) on catalog task form.

I have a requirement where assigned to user can select a device (reference field) value on Catalog Task. I want to make sure when a user picks up a device from reference field pop up, no other user can select the same device until the task is updated by the first user.

Is there any way to restrict other users from seeing the device in reference pop-up when some other user is already trying to use it.

Can we lock? Show Message>

[Brad Bowman]

That selection only exists in the browser session of that user.  You can run an onChange Client Script that updates a field on that record, then the reference qualifier would exclude records with a certain value for this field.  It won't stop more than one user already having the window open then selecting the same record, but the onChange and/or an onSubmit script could do another check before the update is saved making sure the device is still available / wasn't selected by someone else.

[Jags5]

Thanks a lot Brad. I haven't come across such a use case till now. It got me thinking when someone from client team raised this point. I wish there was more documentation from ServiceNow to this end. I will try the options you proposed and let you know if I am successful. Thanks again.