TY - GEN
T1 - Datalog programs over infinite databases, revisited
AU - Cohen, Sara
AU - Gil, Joseph
AU - Zarivach, Evelina
PY - 2007
Y1 - 2007
N2 - This paper's revisit of infinite relational databases, a model traditionally perceived as purely theoretical, was sparked by a concrete implementation setting, and the results obtained here were used in a practical database problem. In the course of implementing a database system for querying Java software, we found that the universe of Java code can be effectively modeled as an infinite database. This modeling makes it possible to distinguish between queries which are "open-ended," that is, whose result may grow as software components are added into the system, and queries which are "closed," in that their result does not change as the software base grows. Further, closed queries can be implemented much more efficiently than open queries. Achievements include an algorithm for distinguishing between these two kinds of queries (we assume that queries are written in Datalog), and an algorithm to generate an efficient evaluation scheme of closed queries, which is a generalization of Vieille's famous QSQR algorithm for top-down evaluation of Datalog programs. A by-product of this work is a rather terse and elegant representation of QSQR.
AB - This paper's revisit of infinite relational databases, a model traditionally perceived as purely theoretical, was sparked by a concrete implementation setting, and the results obtained here were used in a practical database problem. In the course of implementing a database system for querying Java software, we found that the universe of Java code can be effectively modeled as an infinite database. This modeling makes it possible to distinguish between queries which are "open-ended," that is, whose result may grow as software components are added into the system, and queries which are "closed," in that their result does not change as the software base grows. Further, closed queries can be implemented much more efficiently than open queries. Achievements include an algorithm for distinguishing between these two kinds of queries (we assume that queries are written in Datalog), and an algorithm to generate an efficient evaluation scheme of closed queries, which is a generalization of Vieille's famous QSQR algorithm for top-down evaluation of Datalog programs. A by-product of this work is a rather terse and elegant representation of QSQR.
UR - http://www.scopus.com/inward/record.url?scp=38449115385&partnerID=8YFLogxK
U2 - 10.1007/978-3-540-75987-4_3
DO - 10.1007/978-3-540-75987-4_3
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AN - SCOPUS:38449115385
SN - 9783540759867
T3 - Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
SP - 32
EP - 37
BT - Database Programming Languages - 11th International Symposium, DBPL 2007, Revised Selected Papers
PB - Springer Verlag
T2 - 11th International Symposium on Database Programming Languages, DBPL 2007
Y2 - 23 September 2007 through 24 September 2007
ER -