Jim Gray was a real legend in Computer Science and Mathematics and he really has shaped various sectors of Computer Science in ways that live on in his infinite memory.
Although there remains the possibility of him still being found alive, this tragically is disappearing into the mists of deep improbability - he disappeared at the end of January this year on a solo boating trip and the search for him was called off in February.
We all owe our deepest respects to Gray's work (detail of which can be found
here), and it is a credit to him and his family that his work lives on at Microsoft Research.
He will be sorely missed.