This Day in Music reports that the first 45 RPM single was issued by RCA on this day in 1949. BBC and the video above says that the song was Texakana Baby sung by Eddy Arnold. The fellow in the video says it was released on March 1, though.
If the record in the video above is an original, that fellow may want to be a bit more careful with it. But would an original be aqua? It looks like the guy has one of the original record players as well.by