This is so fantastic! I too didn't know all the words, and now I'm entertaining, on the piano, at my mother in law's home for seniors. Other lovely songs I remember from that time were:
Lilli Marlene (underneath the lamplight)
Anniversary Song (Oh! How we danced....)
Smoke gets in your eyes (They asked me how I knew...)
Tennessee waltz (I was waltzing with my darling...)

Fun to trip down memory lane!