{"id":"https://openalex.org/W1985592846","doi":"https://doi.org/10.1016/0012-365x(79)90064-5","title":"Contribution to the theory of data base relations","display_name":"Contribution to the theory of data base relations","publication_year":1979,"publication_date":"1979-01-01","ids":{"openalex":"https://openalex.org/W1985592846","doi":"https://doi.org/10.1016/0012-365x(79)90064-5","mag":"1985592846"},"language":"en","primary_location":{"id":"doi:10.1016/0012-365x(79)90064-5","is_oa":false,"landing_page_url":"https://doi.org/10.1016/0012-365x(79)90064-5","pdf_url":null,"source":{"id":"https://openalex.org/S18902827","display_name":"Discrete Mathematics","issn_l":"0012-365X","issn":["0012-365X","1872-681X"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310320990","host_organization_name":"Elsevier BV","host_organization_lineage":["https://openalex.org/P4310320990"],"host_organization_lineage_names":["Elsevier BV"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Discrete Mathematics","raw_type":"journal-article"},"type":"article","indexed_in":["crossref"],"open_access":{"is_oa":false,"oa_status":"closed","oa_url":null,"any_repository_has_fulltext":false},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5077674638","display_name":"A. B\u00e9k\u00e9ssy","orcid":null},"institutions":[{"id":"https://openalex.org/I7597260","display_name":"Hungarian Academy of Sciences","ror":"https://ror.org/02ks8qq67","country_code":"HU","type":"government","lineage":["https://openalex.org/I7597260"]}],"countries":["HU"],"is_corresponding":true,"raw_author_name":"A. B\u00e9k\u00e9ssy","raw_affiliation_strings":["Computer and Automatition Institute, Hungarian Academy of Sciences, Budapest, Hungary"],"affiliations":[{"raw_affiliation_string":"Computer and Automatition Institute, Hungarian Academy of Sciences, Budapest, Hungary","institution_ids":["https://openalex.org/I7597260"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5089822651","display_name":"J\u00e1nos Demetrovics","orcid":null},"institutions":[{"id":"https://openalex.org/I7597260","display_name":"Hungarian Academy of Sciences","ror":"https://ror.org/02ks8qq67","country_code":"HU","type":"government","lineage":["https://openalex.org/I7597260"]}],"countries":["HU"],"is_corresponding":false,"raw_author_name":"J. Demetrovics","raw_affiliation_strings":["Computer and Automatition Institute, Hungarian Academy of Sciences, Budapest, Hungary"],"affiliations":[{"raw_affiliation_string":"Computer and Automatition Institute, Hungarian Academy of Sciences, Budapest, Hungary","institution_ids":["https://openalex.org/I7597260"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":2,"corresponding_author_ids":["https://openalex.org/A5077674638"],"corresponding_institution_ids":["https://openalex.org/I7597260"],"apc_list":{"value":3000,"currency":"USD","value_usd":3000},"apc_paid":null,"fwci":3.4361,"has_fulltext":false,"cited_by_count":33,"citation_normalized_percentile":{"value":0.91859186,"is_in_top_1_percent":false,"is_in_top_10_percent":true},"cited_by_percentile_year":{"min":94,"max":96},"biblio":{"volume":"27","issue":"1","first_page":"1","last_page":"10"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T11106","display_name":"Data Management and Algorithms","score":0.9983999729156494,"subfield":{"id":"https://openalex.org/subfields/1711","display_name":"Signal Processing"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},"topics":[{"id":"https://openalex.org/T11106","display_name":"Data Management and Algorithms","score":0.9983999729156494,"subfield":{"id":"https://openalex.org/subfields/1711","display_name":"Signal Processing"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T10317","display_name":"Advanced Database Systems and Queries","score":0.9969000220298767,"subfield":{"id":"https://openalex.org/subfields/1705","display_name":"Computer Networks and Communications"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T14500","display_name":"Advanced Mathematical Theories","score":0.9531000256538391,"subfield":{"id":"https://openalex.org/subfields/2610","display_name":"Mathematical Physics"},"field":{"id":"https://openalex.org/fields/26","display_name":"Mathematics"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/base","display_name":"Base (topology)","score":0.8069725036621094},{"id":"https://openalex.org/keywords/mathematics","display_name":"Mathematics","score":0.7644709944725037},{"id":"https://openalex.org/keywords/subject","display_name":"Subject (documents)","score":0.6537041664123535},{"id":"https://openalex.org/keywords/algebraic-number","display_name":"Algebraic number","score":0.5327995419502258},{"id":"https://openalex.org/keywords/type","display_name":"Type (biology)","score":0.4870033860206604},{"id":"https://openalex.org/keywords/algebra-over-a-field","display_name":"Algebra over a field","score":0.4354698657989502},{"id":"https://openalex.org/keywords/discrete-mathematics","display_name":"Discrete mathematics","score":0.3932480216026306},{"id":"https://openalex.org/keywords/combinatorics","display_name":"Combinatorics","score":0.331856906414032},{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.21923723816871643},{"id":"https://openalex.org/keywords/pure-mathematics","display_name":"Pure mathematics","score":0.15535283088684082},{"id":"https://openalex.org/keywords/library-science","display_name":"Library science","score":0.04234442114830017}],"concepts":[{"id":"https://openalex.org/C42058472","wikidata":"https://www.wikidata.org/wiki/Q810214","display_name":"Base (topology)","level":2,"score":0.8069725036621094},{"id":"https://openalex.org/C33923547","wikidata":"https://www.wikidata.org/wiki/Q395","display_name":"Mathematics","level":0,"score":0.7644709944725037},{"id":"https://openalex.org/C2777855551","wikidata":"https://www.wikidata.org/wiki/Q12310021","display_name":"Subject (documents)","level":2,"score":0.6537041664123535},{"id":"https://openalex.org/C9376300","wikidata":"https://www.wikidata.org/wiki/Q168817","display_name":"Algebraic number","level":2,"score":0.5327995419502258},{"id":"https://openalex.org/C2777299769","wikidata":"https://www.wikidata.org/wiki/Q3707858","display_name":"Type (biology)","level":2,"score":0.4870033860206604},{"id":"https://openalex.org/C136119220","wikidata":"https://www.wikidata.org/wiki/Q1000660","display_name":"Algebra over a field","level":2,"score":0.4354698657989502},{"id":"https://openalex.org/C118615104","wikidata":"https://www.wikidata.org/wiki/Q121416","display_name":"Discrete mathematics","level":1,"score":0.3932480216026306},{"id":"https://openalex.org/C114614502","wikidata":"https://www.wikidata.org/wiki/Q76592","display_name":"Combinatorics","level":1,"score":0.331856906414032},{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.21923723816871643},{"id":"https://openalex.org/C202444582","wikidata":"https://www.wikidata.org/wiki/Q837863","display_name":"Pure mathematics","level":1,"score":0.15535283088684082},{"id":"https://openalex.org/C161191863","wikidata":"https://www.wikidata.org/wiki/Q199655","display_name":"Library science","level":1,"score":0.04234442114830017},{"id":"https://openalex.org/C86803240","wikidata":"https://www.wikidata.org/wiki/Q420","display_name":"Biology","level":0,"score":0.0},{"id":"https://openalex.org/C18903297","wikidata":"https://www.wikidata.org/wiki/Q7150","display_name":"Ecology","level":1,"score":0.0},{"id":"https://openalex.org/C134306372","wikidata":"https://www.wikidata.org/wiki/Q7754","display_name":"Mathematical analysis","level":1,"score":0.0}],"mesh":[],"locations_count":1,"locations":[{"id":"doi:10.1016/0012-365x(79)90064-5","is_oa":false,"landing_page_url":"https://doi.org/10.1016/0012-365x(79)90064-5","pdf_url":null,"source":{"id":"https://openalex.org/S18902827","display_name":"Discrete Mathematics","issn_l":"0012-365X","issn":["0012-365X","1872-681X"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310320990","host_organization_name":"Elsevier BV","host_organization_lineage":["https://openalex.org/P4310320990"],"host_organization_lineage_names":["Elsevier BV"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Discrete Mathematics","raw_type":"journal-article"}],"best_oa_location":null,"sustainable_development_goals":[],"awards":[],"funders":[],"has_content":{"pdf":false,"grobid_xml":false},"content_urls":null,"referenced_works_count":10,"referenced_works":["https://openalex.org/W43035074","https://openalex.org/W2074023317","https://openalex.org/W2076452193","https://openalex.org/W2087567316","https://openalex.org/W2185907055","https://openalex.org/W2232207765","https://openalex.org/W2396910560","https://openalex.org/W6601749026","https://openalex.org/W6689392195","https://openalex.org/W6712194897"],"related_works":["https://openalex.org/W3142859449","https://openalex.org/W4317708411","https://openalex.org/W4313433513","https://openalex.org/W2373173956","https://openalex.org/W4390041478","https://openalex.org/W2757872542","https://openalex.org/W1489535460","https://openalex.org/W3214893912","https://openalex.org/W1990741184","https://openalex.org/W566532212"],"abstract_inverted_index":null,"counts_by_year":[{"year":2012,"cited_by_count":2}],"updated_date":"2026-03-10T14:07:55.174380","created_date":"2025-10-10T00:00:00"}