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Logic and databases: a deductive approach
 ACM Computing Surveys
, 1984
"... The purpose of this paper is to show that logic provides a convenient formalism for studying classical database problems. There are two main parts to the paper, devoted respectively to conventional databases and deductive databases. In the first part, we focus on query languages, integrity modeling ..."
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Cited by 143 (2 self)
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The purpose of this paper is to show that logic provides a convenient formalism for studying classical database problems. There are two main parts to the paper, devoted respectively to conventional databases and deductive databases. In the first part, we focus on query languages, integrity modeling and maintenance, query optimization, and data
On The Power Of Languages For The Manipulation Of Complex Objects
 In Proceedings of International Workshop on Theory and Applications of Nested Relations and Complex Objects
, 1993
"... Various models and languages for describing and manipulating hierarchically structured data have been proposed. Algebraic, calculusbased and logicprogramming oriented languages have all been considered. This paper presents a general model for complex objects, and languages for it based on the thre ..."
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Cited by 121 (6 self)
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Various models and languages for describing and manipulating hierarchically structured data have been proposed. Algebraic, calculusbased and logicprogramming oriented languages have all been considered. This paper presents a general model for complex objects, and languages for it based on the three paradigms. The algebraic language generalizes those presented in the literature; it is shown to be related to the functional style of programming advocated by Backus. The notion of domain independence familiar from relational databases is defined, and syntactic restrictions (referred to as safety conditions) on calculus queries are formulated, that guarantee domain independence. The main results are: The domainindependent calculus, the safe calculus, the algebra, and the logicprogramming oriented language have equivalent expressive power. In particular, recursive queries, such as the transitive closure, can be expressed in each of the languages. For this result, the algebra needs the pow...
Efficient Checking of Temporal Integrity Constraints Using Bounded History Encoding
, 1995
"... : We present an efficient implementation method for temporal integrity constraints formulated in Past Temporal Logic. Although the constraints can refer to past states of the database, their checking does not require that the entire database history be stored. Instead, every database state is extend ..."
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Cited by 73 (6 self)
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: We present an efficient implementation method for temporal integrity constraints formulated in Past Temporal Logic. Although the constraints can refer to past states of the database, their checking does not require that the entire database history be stored. Instead, every database state is extended with auxiliary relations that contain the historical information necessary for checking constraints. Auxiliary relations can be implemented as materialized relational views. 1 Introduction Integrity constraints form an essential part of every database application. It is customary to distinguish between two kinds of constraints: static and temporal (or dynamic). Static constraints refer to the current state of the database, e.g.,"every manager is also an employee ", while temporal constraints may refer to past and future states in addition to the current state, e.g., "salaries of employees should never decrease" or "once a student drops out of the Ph.D. program, she should not be readmit...
The Power of Languages for the Manipulation of Complex Values
 VLDB Journal
, 1995
"... Abstract. Various models and languages for describing and manipulating hierarchically structured data have been proposed. Algebraic, calculusbased, and logicprogramming oriented languages have all been considered. This article presents a general model for complex values (i.e., values with hierarc ..."
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Cited by 48 (0 self)
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Abstract. Various models and languages for describing and manipulating hierarchically structured data have been proposed. Algebraic, calculusbased, and logicprogramming oriented languages have all been considered. This article presents a general model for complex values (i.e., values with hierarchical structures), and languages for it based on the three paradigms. The algebraic language generalizes those presented in the literature; it is shown to be related to the functional style of programming advocated by Backus (1978). The notion of domain independence (from relational databases) is defined, and syntactic restrictions (referred to as safety conditions) on calculus queries are formulated to guarantee domain independence. The main results are: The domainindependent calculus, the safe calculus, the algebra, and the logicprogramming oriented language have equivalent expressive power. In particular, recursive queries, such as the transitive closure, can be expressed in each of the languages. For this result, the algebra needs the powerset operation. A more restricted version of safety is presented, such that the restricted safe calculus is equivalent to the algebra without the powerset. The results are extended to the case where arbitrary functions and predicates are used in the languages. Key Words. Database, query language, complex value, complex object, database model.
Integrity verification in knowledge bases
 Logic Programming. Proceedings of the First and Second Russian Conference on Logic Programming, LNCS 592
"... ABSTlZACT In order to faithfully describe reallife applications, knowledge bases have to manage general integrity constraints. In this article, we analyse methods for an efficient verification of integrity constraints in updated knowledge bases. These methods rely on the satisfaction of the integri ..."
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Cited by 28 (3 self)
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ABSTlZACT In order to faithfully describe reallife applications, knowledge bases have to manage general integrity constraints. In this article, we analyse methods for an efficient verification of integrity constraints in updated knowledge bases. These methods rely on the satisfaction of the integrity constraints before the update for simplifying their evaluation in the updated knowledge base. During the last few years, an increasing amount of publications has been devoted to various aspects of this problem. Since they use distinct formalisms and different terminologies, they are di~cult to compare. Moreover, it is often complex to recognize commonalities and to find out whether techniques described in different articles are in principle different. A first part of this report aims at giving a comprehensive stateoftheart in integrity verification. It describes integrity constraint verification techniques in a common formalism. A second part of this report is devoted to comparing several proposals. The differences and similarities between various methods are investigated. 1
Compiling Mappings to Bridge Applications and Databases
 ACM Trans. Database Syst. 33(4), Article
"... Translating data and data access operations between applications and databases is a longstanding data management problem. We present a novel approach to this problem, in which the relationship between the application data and the persistent storage is specified using a declarative mapping, which is ..."
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Cited by 28 (1 self)
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Translating data and data access operations between applications and databases is a longstanding data management problem. We present a novel approach to this problem, in which the relationship between the application data and the persistent storage is specified using a declarative mapping, which is compiled into bidirectional views that drive the data transformation engine. Expressing the application model as a view on the database is used to answer queries, while viewing the database in terms of the application model allows us to leverage view maintenance algorithms for update translation. This approach has been implemented in a commercial product. It enables developers to interact with a relational database via a conceptual schema and an objectoriented programming surface. We outline the implemented system and focus on the challenges of mapping compilation, which include rewriting queries under constraints and supporting nonrelational constructs. Categories and Subject Descriptors:
Groupwise processing of relational queries
 Proceedings of the 1997 VLDB Conference
, 1997
"... In this paper, we define and examine a particular class of queries called group queries. Group queries are natural queries in many decisionsupport applications. The main characteristic of a group query is that it can be executed in a groupbygroup fashion. In other words, the underlying relation( ..."
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Cited by 20 (3 self)
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In this paper, we define and examine a particular class of queries called group queries. Group queries are natural queries in many decisionsupport applications. The main characteristic of a group query is that it can be executed in a groupbygroup fashion. In other words, the underlying relation(s) can be partitioned (based on some set of attributes) into disjoint groups, and each group can be processed separately. We give a syntactic criterion to identify these queries and prove its sufficiency. We also prove the strong result that every group query has an equivalent formulation that satisfies our syntactic criterion. We describe a general evaluation technique for group queries, and demonstrate how an optimizer can determine this plan. We then consider more complex queries whose components are group queries with potentially different partitioning attributes. We give two methods to identify group query components within such a query. We also give some performance results for group queries expressed in standard SQL, comparing a commercial database system with our optimized plan on top of the same commercial system. These results indicate that there are significant potential performance improvements.
On Negation in HiLog
 Journal of Logic Programming
, 1994
"... The logic HiLog of Chen, Kifer and Warren has a second order syntax, while its semantics is first order. HiLog programs with negative literals in the body are considered. A stable model semantics and a wellfounded semantics for this class of programs are defined, and it is shown that these semantic ..."
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Cited by 14 (1 self)
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The logic HiLog of Chen, Kifer and Warren has a second order syntax, while its semantics is first order. HiLog programs with negative literals in the body are considered. A stable model semantics and a wellfounded semantics for this class of programs are defined, and it is shown that these semantics generalize the stable model semantics and the wellfounded semantics, respectively, for rangerestricted normal programs. A second order property called preservation under extensions is proposed and investigated. Preservation under extensions ensures that the semantics of a program is not changed when rules having no symbols in common with the program are appended to the program. It is shown that for normal programs domain independence and preservation under extensions are equivalent, while for HiLog programs preservation under extensions is strictly stronger. Range restrictedness is generalized to HiLog programs in two ways, and it is shown that range restricted HiLog programs are preserv...
Finite Queries do not Have Effective Syntax
, 1995
"... A relational query is called finite, or sometimes safe, iff it yields a finite answer in every database state. The set of finite queries of relational calculus is known to be unsolvable. However, in many cases it is possible to impose syntactical restrictions on the class of queries that guarantee f ..."
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Cited by 14 (3 self)
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A relational query is called finite, or sometimes safe, iff it yields a finite answer in every database state. The set of finite queries of relational calculus is known to be unsolvable. However, in many cases it is possible to impose syntactical restrictions on the class of queries that guarantee finiteness and do not reduce the expressive power of the calculus. We show that unfortunately this is not always the case, as we construct a recursive domain with decidable theory where any solvable (or enumerable, for that matter) subclass of queries either contains an infinite query, or misses a finite one. We show that although any domain can always be extended to a domain with an effective syntax for finite A preliminary version of this paper appeared in the Proc. of the 14th ACM SIGACTSIGMOD SIGART Symp. on Principles of Database Systems, San Jose, CA, May 2225, 1995. y This work has been partially supported by NSF Grant CCR 9403809. z A part of this research was carried out whil...
The Query Model and Query Language of TIGUKAT
, 1993
"... The establishment of a formal object model provides a theoretical foundation to investigate other objectbase features such as query processing. In this report, we present an extensible uniform behavioral object query model for the TIGUKAT object management system. The TIGUKAT object model [PÖS92] is ..."
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Cited by 11 (6 self)
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The establishment of a formal object model provides a theoretical foundation to investigate other objectbase features such as query processing. In this report, we present an extensible uniform behavioral object query model for the TIGUKAT object management system. The TIGUKAT object model [PÖS92] is purely behavioral in nature, supports full encapsulation of objects, defines a clear separation between primitive components such as types, classes, collections, behaviors and functions , and incorporates a uniform semantics over objects which makes it a favorable basis for an extensible query model. Every concept that can be modeled in TIGUKAT has the uniform semantics of a first class object with welldefined behavior. Following this semantics, queries are modeled as type and behavioral extensions to the base object model, thus incorporating queries as an extensible part of the model itself. The complete query model definition presented in this report includes: the type and behavior ex...