Who finds the stats that are read in televised sporting events? How do you get that job and who employs you?

You know how when something rare happens in a televised sporting event and the announcers will read a stat about whatever just happened for example: somebody makes a play that has only happened three times in history and then the announcers read the stat saying that it's only happened three times before and then tell you who else has done it before. Who looks that stat up? What is their job title? Are they employed by the NCAA, NFL, MLB, ect... or CBS, ESPN, FOX, etc... or some outside company that the television networks hire to do live stat research... or something else? Do they do it by writing ad-hoc database queries? Any other information you may have on learning more about this job, if it exists, or how to get it? Thanks!