Database Systems (TODS)


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ACM Transactions on Database Systems (TODS), Volume 7 Issue 4, Dec. 1982

A unifying model of physical databases
D. S. Batory, C. C. Gotlieb
Pages: 509-539
DOI: 10.1145/319758.319760
A unifying model for the study of database performance is proposed. Applications of the model are shown to relate and extend important work concerning batched searching, transposed files, index selection, dynamic hash-based files, generalized...

A practical guide to the design of differential files for recovery of on-line databases
Houtan Aghili
Pages: 540-565
DOI: 10.1145/319758.319762
The concept of a differential file has previously been proposed as an efficient means of collecting database updates for on-line systems. This paper studies the problem of database backup and recovery for such systems, and presents an analytic...

Performance analysis of linear hashing with partial expansions
Per-Åke Larson
Pages: 566-587
DOI: 10.1145/319758.319763
Linear hashing with partial expansions is a new file organization primarily intended for files which grow and shrink dynamically. This paper presents a mathematical analysis of the expected performance of the new scheme. The following measures...

Joined normal form: a storage encoding for relational databasess
E. Babb
Pages: 588-614
DOI: 10.1145/319758.319768
A new on-line query language and storage structure for a database machine is presented. By including a mathematical model in the interpreter the query language has been substantially simplified so that no reference to relation names is...

Mathematical models of database degradation
Daniel P. Heyman
Pages: 615-631
DOI: 10.1145/319758.319771
As data are updated, the initial physical structure of a database is changed and retrieval of specific pieces of data becomes more time consuming. This phenomenon is called database degradation. In this paper two models of database degradation...

Deadlock freedom using edge locks
Henry F. Korth
Pages: 632-652
DOI: 10.1145/319758.319772
We define a series of locking protocols for database systems that all have three main features: freedom from deadlock, multiple granularity, and support for general collections of locking primitives. A rooted directed acyclic graph is used to...

Tree queries: a simple class of relational queries
Nathan Goodman, Oded Shmueli
Pages: 653-677
DOI: 10.1145/319758.319775
One can partition the class of relational database schemas into tree schemas and cyclic schemas. (These are called acyclic hypergraphs and cyclic hypergraphs elsewhere in the literature.) This partition has interesting implications in query...

Query optimization in star computer networks
Larry Kerschberg, Peter D. Ting, S. Bing Yao
Pages: 678-711
DOI: 10.1145/319758.319778
Query processing is investigated for relational databases distributed over several computers organized in a star network. Minimal response-time processing strategies are presented for queries involving the select, project, and join commands....