Yehoshua Chaim Sagiv is a computer scientist

Computer scientist

A computer scientist is a scientist who has acquired knowledge of computer science, the study of the theoretical foundations of information and computation and their application in computer systems....

 and professor of computer science at the Hebrew University of Jerusalem

Hebrew University of Jerusalem

The Hebrew University of Jerusalem ; ; abbreviated HUJI) is Israel's second-oldest university, after the Technion – Israel Institute of Technology. The Hebrew University has three campuses in Jerusalem and one in Rehovot. The world's largest Jewish studies library is located on its Edmond J...

. He obtained his PhD at Princeton University

Princeton University

Princeton University is a private research university located in Princeton, New Jersey, United States. The school is one of the eight universities of the Ivy League, and is one of the nine Colonial Colleges founded before the American Revolution....

 in 1978. His advisor was Jeffrey Ullman

Jeffrey Ullman

Jeffrey David Ullman is a renowned computer scientist. His textbooks on compilers , theory of computation , data structures, and databases are regarded as standards in their fields.-Early life & Career:Ullman received a Bachelor of Science degree in Engineering...

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Sagiv is one of the founders of the field of relational database theory

Database theory

Database theory encapsulates a broad range of topics related to the study and research of the theoretical realm of databases and database management systems....

, and specifically of dependency theory

Dependency theory (database theory)

Dependency theory is a subfield of database theory which studies implication and optimization problems related to logical constraints, commonly called dependencies, on databases....

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He also did seminal work in the areas of semi-structured databases and local-as-view data integration

Data integration

Data integration involves combining data residing in different sources and providing users with a unified view of these data.This process becomes significant in a variety of situations, which include both commercial and scientific domains...

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Currently (2008) he is the most-published author in the ACM Symposium on Principles of Database Systems (with 29 papers published there). He was also the winner of the ACM SIGMOD

SIGMOD

SIGMOD is the Association for Computing Machinery's Special Interest Group on Management of Data, which specializes in large-scale data management problems and databases....

Test of Time Award in 2002.