It may be possible, but to make everything a bit cleaner, maybe you could just create a scripting function that also runs the query, and try to bind the label to a [tt]runScript(…)[/tt] function that calls it?
Otherwise, I’d probably create a custom property on the label (or somewhere else, if this shift is needed in multiple places) called “ShiftId” or whatever, and bind that to a runScript that calls the function, and then reference that property inside of the query.
Regards,