Patrick Eugene O'Neil (1942 – September 20, 2019) was an American computer scientist, an expert on

database In computing, a database is an organized collection of data or a type of data store based on the use of a database management system (DBMS), the software that interacts with end users, applications, and the database itself to capture and a ...

s, and a professor of computer science at the

University of Massachusetts Boston The University of Massachusetts Boston (stylized as UMass Boston) is a Public university, public US-based research university. It is the only public research university in Boston and the third-largest campus in the five-campus University of Ma ...

.Curriculum vitae
retrieved 2010-11-26. He is of Irish descent. O'Neil did his undergraduate studies at the

Massachusetts Institute of Technology The Massachusetts Institute of Technology (MIT) is a Private university, private research university in Cambridge, Massachusetts, United States. Established in 1861, MIT has played a significant role in the development of many areas of moder ...

, receiving a B.S. in mathematics in 1963. After earning a master's degree at the

University of Chicago The University of Chicago (UChicago, Chicago, or UChi) is a Private university, private research university in Chicago, Illinois, United States. Its main campus is in the Hyde Park, Chicago, Hyde Park neighborhood on Chicago's South Side, Chic ...

, he moved to

Rockefeller University The Rockefeller University is a Private university, private Medical research, biomedical Research university, research and graduate-only university in New York City, New York. It focuses primarily on the biological and medical sciences and pro ...

, where he earned a Ph.D. in combinatorial mathematics in 1969 under the supervision of

Gian-Carlo Rota Gian-Carlo Rota (April 27, 1932 – April 18, 1999) was an Italian-American mathematician and philosopher. He spent most of his career at the Massachusetts Institute of Technology, where he worked in combinatorics, functional analysis, proba ...

. He was an assistant professor at MIT from 1970 to 1972, but then left academia for industry, returning in 1988 as a member of the UMass/Boston faculty. He became a full professor in 1996. He wrote highly cited papers on replication in

distributed database A distributed database is a database in which data is stored across different physical locations. It may be stored in multiple computers located in the same physical location (e.g. a data centre); or maybe dispersed over a computer network, netwo ...

s, page replacement strategies for databases,.

SQL Structured Query Language (SQL) (pronounced ''S-Q-L''; or alternatively as "sequel") is a domain-specific language used to manage data, especially in a relational database management system (RDBMS). It is particularly useful in handling s ...

isolation, and database indexing strategies. With Elizabeth O'Neil, he is the author of the database textbook ''Database Principles, Programming, and Performance'' (Morgan Kaufmann, 2nd ed., 2000). O'Neil published the algorithms of the bitmap indices he found working in the CCA Model 204

DBMS In computing, a database is an organized collection of data or a type of data store based on the use of a database management system (DBMS), the software that interacts with end users, applications, and the database itself to capture and ana ...

in the mid-1980s, and implemented

B-tree In computer science, a B-tree is a self-balancing tree data structure that maintains sorted data and allows searches, sequential access, insertions, and deletions in logarithmic time. The B-tree generalizes the binary search tree, allowing fo ...

for that database. This work was first published in 1987. O’Neil invented the Log-Structured Merge Tree (LSM Tree) along with Dieter Gawlick and Edward Cheng in 1991 while spending the summer at Gawlick's database research group at

Digital Equipment Corporation Digital Equipment Corporation (DEC ), using the trademark Digital, was a major American company in the computer industry from the 1960s to the 1990s. The company was co-founded by Ken Olsen and Harlan Anderson in 1957. Olsen was president until ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

. The resulting paper, published in 1996, also included a performance analysis by Elizabeth O'Neil. This access method supports very fast inserts without hobbling lookup times, and now underlies many

NoSQL NoSQL (originally meaning "Not only SQL" or "non-relational") refers to a type of database design that stores and retrieves data differently from the traditional table-based structure of relational databases. Unlike relational databases, which ...

data stores, such as Bigtable, HBase, LevelDB, SQLite4, Tarantool, RocksDB, WiredTiger,

Apache Cassandra Apache Cassandra is a free and open-source software, free and open-source database management system designed to handle large volumes of data across multiple Commodity computing, commodity servers. The system prioritizes availability and scalab ...

, InfluxDB, and ScyllaDB.

References

{{DEFAULTSORT:Oneil, Patrick American computer scientists Massachusetts Institute of Technology School of Science alumni University of Chicago alumni Rockefeller University alumni Massachusetts Institute of Technology faculty University of Massachusetts Boston faculty 1942 births 2019 deaths