Are they the same song? Or am I hallucinating?
Ravel’s Bolero alternates between two themes. Uptown Girl does resemble the first theme.
I’ve also heard it claimed that “Bolero” is the same song as “Memories” (from Cats).
Well, off of the same album (An Innocent Man), Billy Joel uses Beethoven for the chorus of “This Night.”
Well, those three songs only share the first bit of Bolero’s primary melody, approximately:
“uptown girl, she’s been living in an . . .”
and
“Memories, all alone in the moonlight, I . . .”
The harmonies are different, as is the overall song structure, so while they may quote Bolero they are not “the same song”. I could easily believe that Weber and Joel were inspired by Bolero, maybe even deliberately quoted Ravel, but it’s a stretch to say more than that.
Ravel’s Bolero, composed in 1928, is not a song. It is an orchestral piece, more specificially, it is a sylized bolero for orchestra, the bolero itself being a Spanish dance. No singing is involved, neither is any sort of song form.
That’s true, of course, if we must be literal. But needlessly haughty comments like that are what give we Classical folk a bad name with the young’uns, Knorf. 
Gee, Mr. Knorf, thanks! I’ve never heard of a sylized bolero before! crosses legs and looks up expectantly
Hey, what about that Bach’s Minuet! It’s a total ripoff of Lover’s Concerto!