Sammy Davis, Jr. was a legendary American singer-entertainer in both Reno and Las Vegas during the 1950s and 1960s. Sammy was so popular, in fact, he was included in the holosuite program Bashir 62, a 24th century rendition of 1962. At the time, he was close friends with Frank Sinatra, Dean Martin, Peter Lawford, Joey Bishop, and was incorporated as a "tight" friend of Vic Fontaine's.
That year, Vic planned on flying up to Tahoe for a couple days to see Sammy perform at Cal-Neva. While there, Vic intended to introduce Nog to Sammy.
Upon telling Ezri Dax this, Ezri interpreted it as a ploy by Vic to use Sammy to convince Nog that it was time to leave the holosuite, Nog's chosen rehabilitation facility following the loss of his leg. Ezri's revelation, however, was not Vic's intention, which ultimately forced Vic to cancel his trip to see Sammy perform and realize that he needed to confront Nog about overstaying his holosuite visit. (DS9: "It's Only a Paper Moon")
According to the Star Trek Encyclopedia, 4th ed., vol. 1, p. 186, the birth and death years of Sammy Davis, Jr. were 1925 and 1990, respectively.
Davis, Sinatra, Martin, Lawford and Bishop were together members of the legendary Rat Pack.
His last name was not mentioned on screen.