Thanks to bluesinorbit for the You Tube
Where or When was composed and written by Rogers and Hart originally for the musical Babes in Arms. This version was recorded by Art Tatum for Norman Granz in 1953. I have it on the Art Tatum Pablo Solo Masterpieces Vol 3 track 2 on Compact Disc. Listening to the Tatum repertoire, I realize that he was the first one to put together a definitive Great American Song Book. His Solo Masterpieces reissued on Pablo are the Great American Song Book.