Implementation of logical query languages for databases
ACM Transactions on Database Systems (TODS)
An amateur's introduction to recursive query processing strategies
SIGMOD '86 Proceedings of the 1986 ACM SIGMOD international conference on Management of data
Traversal recursion: a practical approach to supporting recursive applications
SIGMOD '86 Proceedings of the 1986 ACM SIGMOD international conference on Management of data
A study of transitive closure as a recursion mechanism
SIGMOD '87 Proceedings of the 1987 ACM SIGMOD international conference on Management of data
A necessary condition for a doubly recursive rule to be equivalent to a linear recursive rule
SIGMOD '87 Proceedings of the 1987 ACM SIGMOD international conference on Management of data
Principles of database and knowledge-base systems, Vol. I
Principles of database and knowledge-base systems, Vol. I
An approach to the recursive retrieval problem in the relational database
Communications of the ACM
A logical language for data and knowledge bases
A logical language for data and knowledge bases
Relational databases and knowledge bases
Relational databases and knowledge bases
Explicit control of logic programs through rule algebra
Proceedings of the seventh ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Design of an external schema facility to define and process recursive structures
ACM Transactions on Database Systems (TODS)
The design and implementation of INGRES
ACM Transactions on Database Systems (TODS)
Equivalence of Relational Algebra and Relational Calculus Query Languages Having Aggregate Functions
Journal of the ACM (JACM)
Logic and Databases: A Deductive Approach
ACM Computing Surveys (CSUR)
A relational model of data for large shared data banks
Communications of the ACM
Universality of data retrieval languages
POPL '79 Proceedings of the 6th ACM SIGACT-SIGPLAN symposium on Principles of programming languages
Horn clauses and the fixpoint query hierarchy
PODS '82 Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems
Alpha: An Extension of Relational Algebra to Express a Class of Recursive Queries
Proceedings of the Third International Conference on Data Engineering
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Different classes of recursive queries in the relational databases are identified. It is shown that existing proposals to extend the relational query languages are either not powerful enough to express queries in many of these classes or use nonfirst normal form constructs. RQL, a recursive database query language that can be used to express recursive queries on all the classes identified, is presented. RQL is based on the relational algebra. In addition to functions that correspond to the standard and extended relational algebra operators, RQL supports functions required to express general recursive queries. The elements of RQL and the ways in which they are used to formulate complicated, but useful, recursive queries are described. The effects of the extensions embodied in RQL on the termination of recursive query evaluation are discussed.