e-commerce. Every time we use an
ATM, reserve a seat on an airplane, or
purchase an item on the Web, we are
relying on the mechanisms Jim first
developed 30-odd years ago. These
techniques ensure that the “right”
thing always happens—even in the
presence of software and hardware
failure. While they seem second-nature
to us today, when Jim conceived them
they required very deep insight into the
complexities of concurrently executing
queries and updates against a shared
database system.
Later in his career, Jim became interested in helping natural scientists
with their work. He pioneered putting
astronomy observation data into a database system. In this way scientists
could query their data in SQL, rather
than having to write custom programs
in C++ or some other general-purpose
language. Implementation of this idea
for the Sloan Digital Sky Survey (www.
sdss.org/) has resulted in more than
2,000 astronomy publications based
on querying this data set through SQL.
Jim received his bachelor’s and Ph. D.
degrees from the University of California, Berkeley, in 1966 and 1969, respec-
tively. Soon after receiving his Ph.D. he
joined the IBM San Jose Research Laboratory (now known as the IBM Almaden
Research Center) where he helped lead
the design and development of System
R, one of the first database systems to
use the relational data model. In 1988,
System R (along with INGRES, for the
INteractive Graphics REtrieval System,
project at Berkeley) was honored with
the ACM Software Systems Award for
pioneering development of relational
database systems. It was as part of the
System R project that Jim first developed the notion of what it means for
transactions to be “serializable”; that is,
they produce the same outcome as the
serial ordering of the transactions. He
also developed the connection between
serializability and database consistency
and how a simple protocol known as
“two-phase locking” could be used t o
ensure that two or more transactions are
serializable with respect to each other
without the user having to understand
the semantics of the transactions.
From the time he left IBM in 1980
to his joining Microsoft in 1995,
Jim worked for Tandem Computers
(1980–1990) on the parallel relational
database system Non-Stop SQL and
at Digital Equipment Corporation
(1990–1995). Over the course of his
career Jim also made numerous technical contributions beyond his work
on transactions, including database
system architectures and algorithms,
fault tolerance, input/output architectures, parallel database systems, database system performance evaluation
and benchmarking, multidimensional
data analysis, and e-science, including
the TerraServer (www.terraserver-usa.
com) and the Sloan Digital Sky Survey
project. When he disappeared at sea in
2007, he held the title of Technical Fel-
low at Microsoft.
That disappearance spurred the
computer science community to action,
and a massive amateur search effort
was pulled together to augment the professional one launched by the U. S. Coast
Guard. This effort entailed retargeting
satellites to sweep the region of interest
and posting the imagery on the Amazon
Mechanical Turk site ( www.mturk.com)
so the distributed community could examine it in parallel to look for his sailboat, Tenacious. Possible sightings were
then examined by experts in image rec-
ognition. It is the hope of the community that this imagery workflow will be
automated and performed in real time
during future searches. Parallel efforts
searched for wreckage along the entire
length of the California coastline and
posted flyers at every marina in California. No trace of Jim’s boat was ever
found. An extensive underwater search
was equally unsuccessful. Hence, it is
likely that we will never know what happened to Tenacious, and the loss of Jim
Gray will remain a mystery.
I (Michael) first met Jim while I
was a struggling assistant professor at
Berkeley in 1971. He was instrumental in helping me do the research that
led to my first publication, which dealt
with a simplification of Jay Forrester’s
model of an urban area. I am forever
grateful for his help motivating me in
the publish-or-perish world of an assistant professor.
Jim was obviously brilliant, as anyone who talked to him quickly realized.
However, he also read widely and knew
a lot about a lot of things. In fact, he is
one of the few people I have found to be
intellectually intimidating. Moreover,
he was always willing to read papers
that other researchers sent him and
