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Querying Relational Databases without Explicit Joins [chapter]

Ramon Lawrence, Ken Barker
2002 Lecture Notes in Computer Science  
This translation involves automatically determining attribute and relation mappings and join conditions.  ...  In this work, we propose a semantic query language for graphically querying relational database systems that allows a user to query the database by semantics instead of structure.  ...  and appropriate join conditions.  ... 
doi:10.1007/3-540-46140-x_22 fatcat:twae5vsmnnclbey3z5am5vagxm

Adding relational query facilities to software development environments [chapter]

Susan Horwitz
1988 Lecture Notes in Computer Science  
A better approach would be to take advantage of current database technology, basing the query facility on the relational database model [4]. Under this model, arbitrm-y queries can be written by  ...  We extend the definition of implicit relations and show how they can be used to support relational query facilities in software development environments without giving up the use of nonrelational data  ...  handles queries with both implicit and explicit relations.  ... 
doi:10.1007/3-540-19027-9_18 fatcat:iy3cf3grzncrhaodii27sbi4ty

Adding relational query facilities to software development environments

Susan Horwitz
1990 Theoretical Computer Science  
giving up traditio cry facilities without relations.  ...  Currently available database management syste implicit relations; thus, rather than makin system, our implementation includes (explicit) relations.  ... 
doi:10.1016/0304-3975(90)90146-9 fatcat:7k7a6xfcbbchdh5tnw3ik5r52u

Abstract Versus Concrete Temporal Query Languages [chapter]

Jan Chomicki, David Toman
2016 Encyclopedia of Database Systems  
SYNONYMS historical query languages DEFINITION Temporal query languages are a family of query languages designed to query (and access in general) time-dependent information stored in temporal databases  ...  The languages are commonly defined as extensions of standard query languages for non-temporal databases with temporal features.  ...  Without the insertion of the explicit coalescing operators, the query is incorrect.  ... 
doi:10.1007/978-1-4899-7993-3_1559-2 fatcat:p7isrdz435gvhmjfnonm2n7evi

An SQL extension supporting user viewpoints [chapter]

Giuseppe Bellavia, Dario Maio, Stefano Rizzi
1995 Lecture Notes in Computer Science  
even if the necessary joins are not explicitly formulated (query inference problem).  ...  Our approach to the definition of user viewpoint relations aims at reducing the global cost of query formulation, that is, the number of joins which must be explicitly written.  ...  The queries which are not implicitly supported can be formulated by means of explicit joins. The user viewpoint approach could be integrated within a graphic database development tool.  ... 
doi:10.1007/bfb0049131 fatcat:qcgv2nbdz5avvkiemddefrfnc4

Extending a relational database with deferred referential integrity checking and intelligent joins

Stephanie Cammarata, Prasadram Ramachandra, Darrell Shane
1989 SIGMOD record  
These facilities are made possible by explicit representation of database semantics combined with a relational schema.  ...  Two categories of functionality sre problematic for such users: (1) updating a database without violating integrity constraints imposed by the domain and (2) using join operations to retrieve data from  ...  join clauses; 3) a query with no join clauses where the relations lie on a network path, or 4) a query (with or without join clauses) where the relations do not lie on a network path.  ... 
doi:10.1145/66926.66935 fatcat:wqbgloluq5godbxq5v2ps6ewjy

Extending a relational database with deferred referential integrity checking and intelligent joins

Stephanie Cammarata, Prasadram Ramachandra, Darrell Shane
1989 Proceedings of the 1989 ACM SIGMOD international conference on Management of data - SIGMOD '89  
These facilities are made possible by explicit representation of database semantics combined with a relational schema.  ...  Two categories of functionality sre problematic for such users: (1) updating a database without violating integrity constraints imposed by the domain and (2) using join operations to retrieve data from  ...  join clauses; 3) a query with no join clauses where the relations lie on a network path, or 4) a query (with or without join clauses) where the relations do not lie on a network path.  ... 
doi:10.1145/67544.66935 dblp:conf/sigmod/CammarataRS89 fatcat:uirofh7clzahxjnubf3zqte2bm

Optimizing relational algebra operations using generic equivalence discriminators and lazy products

Fritz Henglein
2010 Proceedings of the ACM SIGPLAN 2010 workshop on Partial evaluation and program manipulation - PEPM '10  
In particular, queries can still be formulated naively, using filter, map and product without an explicit join operation, yet garner the advantages of efficient join-algorithms during evaluation.  ...  The techniques subsume many of the optimization techniques based on relational algebra equalities, without need for a query preprocessing phase.  ...  In the end this will let us execute relational algebra queries efficiently without requiring an explicit join operation. We present the core ideas and their realizations as code.  ... 
doi:10.1145/1706356.1706372 dblp:conf/pepm/Henglein10 fatcat:3ws57kojjjejxmgnnybso7nbu4

Language-integrated query with ordering, grouping and outer joins (poster paper)

Tatsuya Katsushima, Oleg Kiselyov
2017 Proceedings of the 2017 ACM SIGPLAN Workshop on Partial Evaluation and Program Manipulation - PEPM 2017  
To access relational database systems, queries are eventually translated into well-formed, well-typed and efficient SQL.  ...  However, most existing language-integrated query systems implement only a small subset of relational operations supported by modern databases.  ...  Conclusions We have described the extension of QUEΛ with ordering and outer joins, giving a short summary of the normalization process and the type system.  ... 
doi:10.1145/3018882.3018893 fatcat:djdmafhhqzcaliel2gcns5hb5q

Query Migration from Object Oriented World to Semantic World

Nassima Soussi, Mohamed Bahaj
2016 International Journal of Interactive Multimedia and Artificial Intelligence  
(SELECT clause, FROM clause, FILTER constraint, implicit/ explicit join and union/intersection SELECT queries).  ...  In the last decades, object-oriented approach was able to take a large share of databases market aiming to design and implement structured and reusable software through the composition of independent elements  ...  The OQL queries listed in this example have the types: Simple query (SELECT FROM clause with/without WHERE clause), implicit and explicit join, Union and intersection SELECT queries.  ... 
doi:10.9781/ijimai.2016.373 fatcat:iyrk72b2ufbvvb5irtix5vejri

Materializing multi-relational databases from the web using taxonomic queries

Matthew Michelson, Sofus A. Macskassy, Steven N. Minton, Lise Getoor
2011 Proceedings of the fourth ACM international conference on Web search and data mining - WSDM '11  
Beyond discovering the relations that define single tables, our approach discovers and leverages "within column" set membership relations, and discovers relations across the extracted tables (e.g., joins  ...  By leveraging within-column relations our method can extract table instances that are ambiguous or rare, and by discovering joins, our method generates truly multi-relational output.  ...  Finally, the JoinFinder finds both "explicit" joins and "implicit" joins across the cleaned tables. The result is a materialized database related to the set of input taxonomic queries.  ... 
doi:10.1145/1935826.1935885 dblp:conf/wsdm/MichelsonMMG11 fatcat:dnbhewbuovdfvbaupxafez75dq

Achievements and Weaknesses of Object-Oriented Databases

Sikha Bagui
2003 Journal of Object Technology  
before object-oriented database technology can become as widespread as relational databases.  ...  Object-oriented database systems began developing in the mid-80's out of a necessity to meet the requirements of applications beyond the data processing applications which were [are] served by relational  ...  Since two classes in an OODB may have corresponding pairs of attributes, the relational join (or, explicit join) may still be necessary in OODBs.  ... 
doi:10.5381/jot.2003.2.4.c2 fatcat:wk265lulkvfhdjdy7lvh4bbvfu

NoXperanto: Crowdsourced Polyglot Persistence

Antonio Maccioni, Orlando Cassano, Yongming Luo, Juan Castrejón, Genoveva Vargas-Solar
2014 POLIBITS Research Journal on Computer Science and Computer Engineering With Applications  
In particular, queries results are used to: (i) help non-expert users in using the multi-database environment and (ii) improve performances of the multi-database environment, which not only uses disk and  ...  The main contribution of NoXperanto is the ability to solve complex queries involving different data stores by exploiting queries from expert users (i.e. a crowd of database administrators, data engineers  ...  In the explicit manner, the user can define how two classes of entities in different databases are related.  ... 
doi:10.17562/pb-50-6 fatcat:d54zcvm6jvfbboobuzd4yijvtu

Database Technology for Processing Temporal Data (Invited Paper)

Michael H. Böhlen, Anton Dignös, Johann Gamper, Christian S. Jensen, Michael Wagner
2018 International Symposium/Workshop on Temporal Representation and Reasoning  
There has also been a proposal for a more fundamental and comprehensive solution for sequenced temporal queries, which allows a tight integration into relational database systems, thereby taking advantage  ...  of existing query optimization and evaluation technologies.  ...  achieve systematic and comprehensive support for so-called sequenced temporal queries in relational database engines without limiting the use of queries with so-called nonsequenced semantics.  ... 
doi:10.4230/lipics.time.2018.2 dblp:conf/time/BohlenDGJ18 fatcat:j3kfsfijijfi7o6wpsytjbnw7u

Join operations in temporal databases

Dengfeng Gao, Christian S. Jensen, Richard T. Snodgrass, Michael D. Soo
2005 The VLDB journal  
Joins are arguably the most important relational operators. Poor implementations are tantamount to computing the Cartesian product of the input relations.  ...  First, conventional techniques are designed for the evaluation of joins with equality predicates rather than the inequality predicates prevalent in valid-time queries.  ...  We also thank Wei Li and Joseph Dunn for their help in implementing the temporal join algorithms.  ... 
doi:10.1007/s00778-003-0111-3 fatcat:lgdvkgkftzglbodt3jlx5jtrra
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