Interesting to see so many "versions".

The last one to write above this comment phonetically remembers the song, but the name is Johnny Rübeck and yes the word is "speck" (pronounced as Tekbird writes above: schpeck--which always goes with sauerkraut and sausage ;-)

And Johnny was definitely a Dutchman--not a boy.
And the boy who came into the store, well, I guess he could be fat--if it helps with the poetic scansion. Here I don't think it matters much--but for a camp song, it might be kinder to just let him be a "normal" boy.

One day a boy came walking.
He walked into the store
He bought a pack of sausages
And placed them on the floor,
Then he began to whistle
He whistled up a tune,
And all the little sausages,
They danced around the room.

Cheers!