{"id":"https://openalex.org/W1991388416","doi":"https://doi.org/10.1016/s0304-3975(97)00090-x","title":"Models of approximation in databases","display_name":"Models of approximation in databases","publication_year":1998,"publication_date":"1998-01-01","ids":{"openalex":"https://openalex.org/W1991388416","doi":"https://doi.org/10.1016/s0304-3975(97)00090-x","mag":"1991388416"},"language":"en","primary_location":{"id":"doi:10.1016/s0304-3975(97)00090-x","is_oa":true,"landing_page_url":"https://doi.org/10.1016/s0304-3975(97)00090-x","pdf_url":"https://www.sciencedirect.com/science/article/pii/S030439759700090X/pdf","source":{"id":"https://openalex.org/S90727058","display_name":"Theoretical Computer Science","issn_l":"0304-3975","issn":["0304-3975","1879-2294"],"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":"Theoretical Computer Science","raw_type":"journal-article"},"type":"article","indexed_in":["crossref"],"open_access":{"is_oa":true,"oa_status":"bronze","oa_url":"https://www.sciencedirect.com/science/article/pii/S030439759700090X/pdf","any_repository_has_fulltext":false},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5069883356","display_name":"Leonid Libkin","orcid":"https://orcid.org/0000-0002-6698-2735"},"institutions":[{"id":"https://openalex.org/I72090969","display_name":"Nokia (United States)","ror":"https://ror.org/038km2573","country_code":"US","type":"company","lineage":["https://openalex.org/I2738502077","https://openalex.org/I72090969"]}],"countries":["US"],"is_corresponding":true,"raw_author_name":"Leonid Libkin","raw_affiliation_strings":["Bell Laboratories, 600 Mountain Avenue, Murray Hill, NJ 07974, USA","Bell Laboratories//600 Mountain Avenue//Murray Hill, NJ 07974 USA"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Bell Laboratories, 600 Mountain Avenue, Murray Hill, NJ 07974, USA","institution_ids":[]},{"raw_affiliation_string":"Bell Laboratories//600 Mountain Avenue//Murray Hill, NJ 07974 USA","institution_ids":["https://openalex.org/I72090969"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":1,"corresponding_author_ids":["https://openalex.org/A5069883356"],"corresponding_institution_ids":["https://openalex.org/I72090969"],"apc_list":{"value":2600,"currency":"USD","value_usd":2600},"apc_paid":null,"fwci":0.0,"has_fulltext":true,"cited_by_count":4,"citation_normalized_percentile":{"value":0.17694654,"is_in_top_1_percent":false,"is_in_top_10_percent":false},"cited_by_percentile_year":null,"biblio":{"volume":"190","issue":"2","first_page":"167","last_page":"210"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T10317","display_name":"Advanced Database Systems and Queries","score":0.9994999766349792,"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"}},"topics":[{"id":"https://openalex.org/T10317","display_name":"Advanced Database Systems and Queries","score":0.9994999766349792,"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/T11106","display_name":"Data Management and Algorithms","score":0.9980000257492065,"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/T11010","display_name":"Logic, Reasoning, and Knowledge","score":0.9977999925613403,"subfield":{"id":"https://openalex.org/subfields/1702","display_name":"Artificial Intelligence"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/universality","display_name":"Universality (dynamical systems)","score":0.8115653395652771},{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.6203060746192932},{"id":"https://openalex.org/keywords/database","display_name":"Database","score":0.5662874579429626},{"id":"https://openalex.org/keywords/syntax","display_name":"Syntax","score":0.5086046457290649},{"id":"https://openalex.org/keywords/semantics","display_name":"Semantics (computer science)","score":0.41221147775650024},{"id":"https://openalex.org/keywords/theoretical-computer-science","display_name":"Theoretical computer science","score":0.39717555046081543},{"id":"https://openalex.org/keywords/artificial-intelligence","display_name":"Artificial intelligence","score":0.25296318531036377},{"id":"https://openalex.org/keywords/programming-language","display_name":"Programming language","score":0.22490864992141724}],"concepts":[{"id":"https://openalex.org/C183992945","wikidata":"https://www.wikidata.org/wiki/Q2495574","display_name":"Universality (dynamical systems)","level":2,"score":0.8115653395652771},{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.6203060746192932},{"id":"https://openalex.org/C77088390","wikidata":"https://www.wikidata.org/wiki/Q8513","display_name":"Database","level":1,"score":0.5662874579429626},{"id":"https://openalex.org/C60048249","wikidata":"https://www.wikidata.org/wiki/Q37437","display_name":"Syntax","level":2,"score":0.5086046457290649},{"id":"https://openalex.org/C184337299","wikidata":"https://www.wikidata.org/wiki/Q1437428","display_name":"Semantics (computer science)","level":2,"score":0.41221147775650024},{"id":"https://openalex.org/C80444323","wikidata":"https://www.wikidata.org/wiki/Q2878974","display_name":"Theoretical computer science","level":1,"score":0.39717555046081543},{"id":"https://openalex.org/C154945302","wikidata":"https://www.wikidata.org/wiki/Q11660","display_name":"Artificial intelligence","level":1,"score":0.25296318531036377},{"id":"https://openalex.org/C199360897","wikidata":"https://www.wikidata.org/wiki/Q9143","display_name":"Programming language","level":1,"score":0.22490864992141724},{"id":"https://openalex.org/C121332964","wikidata":"https://www.wikidata.org/wiki/Q413","display_name":"Physics","level":0,"score":0.0},{"id":"https://openalex.org/C62520636","wikidata":"https://www.wikidata.org/wiki/Q944","display_name":"Quantum mechanics","level":1,"score":0.0}],"mesh":[],"locations_count":3,"locations":[{"id":"doi:10.1016/s0304-3975(97)00090-x","is_oa":true,"landing_page_url":"https://doi.org/10.1016/s0304-3975(97)00090-x","pdf_url":"https://www.sciencedirect.com/science/article/pii/S030439759700090X/pdf","source":{"id":"https://openalex.org/S90727058","display_name":"Theoretical Computer Science","issn_l":"0304-3975","issn":["0304-3975","1879-2294"],"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":"Theoretical Computer Science","raw_type":"journal-article"},{"id":"pmh:oai:CiteSeerX.psu:10.1.1.498.3229","is_oa":false,"landing_page_url":"http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.498.3229","pdf_url":null,"source":null,"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"http://homepages.inf.ed.ac.uk/libkin/papers/icdt95.pdf","raw_type":"text"},{"id":"pmh:oai:CiteSeerX.psu:10.1.1.648.5778","is_oa":false,"landing_page_url":"http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.648.5778","pdf_url":null,"source":null,"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"http://homepages.inf.ed.ac.uk/libkin/papers/tcs98.pdf","raw_type":"text"}],"best_oa_location":{"id":"doi:10.1016/s0304-3975(97)00090-x","is_oa":true,"landing_page_url":"https://doi.org/10.1016/s0304-3975(97)00090-x","pdf_url":"https://www.sciencedirect.com/science/article/pii/S030439759700090X/pdf","source":{"id":"https://openalex.org/S90727058","display_name":"Theoretical Computer Science","issn_l":"0304-3975","issn":["0304-3975","1879-2294"],"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":"Theoretical Computer Science","raw_type":"journal-article"},"sustainable_development_goals":[{"display_name":"Quality Education","id":"https://metadata.un.org/sdg/4","score":0.7300000190734863}],"awards":[],"funders":[],"has_content":{"pdf":true,"grobid_xml":true},"content_urls":{"pdf":"https://content.openalex.org/works/W1991388416.pdf","grobid_xml":"https://content.openalex.org/works/W1991388416.grobid-xml"},"referenced_works_count":47,"referenced_works":["https://openalex.org/W592225295","https://openalex.org/W956288144","https://openalex.org/W1486310914","https://openalex.org/W1503312825","https://openalex.org/W1509251869","https://openalex.org/W1520355364","https://openalex.org/W1529395537","https://openalex.org/W1541134641","https://openalex.org/W1544662935","https://openalex.org/W1558832481","https://openalex.org/W1578831036","https://openalex.org/W1867190418","https://openalex.org/W1945946994","https://openalex.org/W1980238601","https://openalex.org/W1990391007","https://openalex.org/W1994581962","https://openalex.org/W1996863624","https://openalex.org/W2003017562","https://openalex.org/W2021257181","https://openalex.org/W2029138494","https://openalex.org/W2058366603","https://openalex.org/W2066837227","https://openalex.org/W2070985734","https://openalex.org/W2074896448","https://openalex.org/W2080430146","https://openalex.org/W2089781037","https://openalex.org/W2096744626","https://openalex.org/W2098656960","https://openalex.org/W2118556647","https://openalex.org/W2123378463","https://openalex.org/W2130872776","https://openalex.org/W2139385511","https://openalex.org/W2142864156","https://openalex.org/W2153320571","https://openalex.org/W2339920159","https://openalex.org/W4206031975","https://openalex.org/W6629123387","https://openalex.org/W6630603293","https://openalex.org/W6631018607","https://openalex.org/W6631477497","https://openalex.org/W6632650452","https://openalex.org/W6634515109","https://openalex.org/W6639188414","https://openalex.org/W6640619663","https://openalex.org/W6669216124","https://openalex.org/W6674733845","https://openalex.org/W6674862797"],"related_works":["https://openalex.org/W3115068090","https://openalex.org/W332573842","https://openalex.org/W2204741347","https://openalex.org/W2170133876","https://openalex.org/W1587914261","https://openalex.org/W2370848225","https://openalex.org/W2090814745","https://openalex.org/W2154994723","https://openalex.org/W219524091","https://openalex.org/W2991618286"],"abstract_inverted_index":null,"counts_by_year":[],"updated_date":"2026-07-31T08:31:51.225901","created_date":"2025-10-10T00:00:00"}