Resource Officers in School

Is having security officers, also know as resource officers, at school helpful? Does it make the rate of violence  go down? Kids are still getting into fights. For example at school, there are videos of fights going around, and people still asking for video of fights from months ago. In the fight videos, there are little to no staff for most of the duration of the fight. At Hiram Johnson High School, there is only one resource officer around campus. A fight happened after school and the cops had to be called, because there weren't enough officers or staff around. A kid got into a fight because a gang of kids knew he was from a different country. A lot of kids ran away, but one kid was caught and was arrested. My dad had to get out of our car and help along with other teachers that were on their way home. Not a lot of kids were caught and as soon as the police showed up a kid already had a bloody nose, and most of the kids were already down the street running. Having only one resource officer is not helpful and I am not sure if more would be helpful. Students will continue to have fights no matter what sort of "security" there is.