Multiple realities
(covers information from several alternate timelines)
David Rossi (also known as Dave Rossi) was a Starfleet officer in the 24th century.
In 2353, he was listed as a Starfleet Operational Support Services officer on the directory placard at Starbase 32, Maxia sector. His office was located in room #35951. (TNG: "Violations", directory)
In 2372, he was listed as a Starfleet Command officer on the dedication plaque of the USS Enterprise-E. (Star Trek: First Contact, dedication plaque)
In an unknown, alternate future timeframe, he was listed as an Advanced Technologies officer on the dedication plaque of the USS Pasteur. (TNG: "All Good Things..." dedication plaque)
This character was only mentioned in writing.