How does traccar determine if device entered geofence

I am using mysql as my database. If I added a polygon geofence, I can easily convert it to geometry type to easily determine outside and inside points. But the problem is the circle geofence data cannot be converted to geoetry using mysql's st_geom_from_text. Do traccar determine outside and inside points separately for circle and polygon geofences? Or it uses just one query?

Traccar calculates geofencing in Java code, not database. There is separate code for polygons and circles.