{"id":"https://openalex.org/W2065869347","doi":"https://doi.org/10.1016/0096-0551(90)90011-d","title":"An extension of SQL for querying graph relations","display_name":"An extension of SQL for querying graph relations","publication_year":1990,"publication_date":"1990-01-01","ids":{"openalex":"https://openalex.org/W2065869347","doi":"https://doi.org/10.1016/0096-0551(90)90011-d","mag":"2065869347"},"language":"en","primary_location":{"id":"doi:10.1016/0096-0551(90)90011-d","is_oa":false,"landing_page_url":"https://doi.org/10.1016/0096-0551(90)90011-d","pdf_url":null,"source":{"id":"https://openalex.org/S181974911","display_name":"Computer Languages","issn_l":"0096-0551","issn":["0096-0551","1873-6742"],"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":"Computer Languages","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/A5023921545","display_name":"Joachim Biskup","orcid":"https://orcid.org/0000-0001-5281-1567"},"institutions":[{"id":"https://openalex.org/I155765044","display_name":"University of Hildesheim","ror":"https://ror.org/02f9det96","country_code":"DE","type":"education","lineage":["https://openalex.org/I155765044"]}],"countries":["DE"],"is_corresponding":false,"raw_author_name":"Joachim Biskup","raw_affiliation_strings":["Institut f\u00fcr Informatik, Universit\u00e4t Hildesheim, Samelsonplatz 1, D-3200 Hildesheim, West Germany"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Institut f\u00fcr Informatik, Universit\u00e4t Hildesheim, Samelsonplatz 1, D-3200 Hildesheim, West Germany","institution_ids":["https://openalex.org/I155765044"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5029906184","display_name":"Uwe R\u00e4sch","orcid":null},"institutions":[{"id":"https://openalex.org/I155765044","display_name":"University of Hildesheim","ror":"https://ror.org/02f9det96","country_code":"DE","type":"education","lineage":["https://openalex.org/I155765044"]}],"countries":["DE"],"is_corresponding":false,"raw_author_name":"Uwe R\u00e4sch","raw_affiliation_strings":["Institut f\u00fcr Informatik, Universit\u00e4t Hildesheim, Samelsonplatz 1, D-3200 Hildesheim, West Germany"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Institut f\u00fcr Informatik, Universit\u00e4t Hildesheim, Samelsonplatz 1, D-3200 Hildesheim, West Germany","institution_ids":["https://openalex.org/I155765044"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5033629708","display_name":"Holger Stiefeling","orcid":null},"institutions":[{"id":"https://openalex.org/I155765044","display_name":"University of Hildesheim","ror":"https://ror.org/02f9det96","country_code":"DE","type":"education","lineage":["https://openalex.org/I155765044"]}],"countries":["DE"],"is_corresponding":false,"raw_author_name":"Holger Stiefeling","raw_affiliation_strings":["Institut f\u00fcr Informatik, Universit\u00e4t Hildesheim, Samelsonplatz 1, D-3200 Hildesheim, West Germany"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Institut f\u00fcr Informatik, Universit\u00e4t Hildesheim, Samelsonplatz 1, D-3200 Hildesheim, West Germany","institution_ids":["https://openalex.org/I155765044"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":3,"corresponding_author_ids":[],"corresponding_institution_ids":[],"apc_list":null,"apc_paid":null,"fwci":1.4773,"has_fulltext":false,"cited_by_count":12,"citation_normalized_percentile":{"value":0.85081506,"is_in_top_1_percent":false,"is_in_top_10_percent":false},"cited_by_percentile_year":null,"biblio":{"volume":"15","issue":"2","first_page":"65","last_page":"82"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T10317","display_name":"Advanced Database Systems and Queries","score":0.9998999834060669,"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":0.9998999834060669,"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/T10215","display_name":"Semantic Web and Ontologies","score":0.9994999766349792,"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"}},{"id":"https://openalex.org/T11106","display_name":"Data Management and Algorithms","score":0.9986000061035156,"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"}}],"keywords":[{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.894889235496521},{"id":"https://openalex.org/keywords/sql","display_name":"SQL","score":0.7436736822128296},{"id":"https://openalex.org/keywords/expressive-power","display_name":"Expressive power","score":0.6218501925468445},{"id":"https://openalex.org/keywords/graph","display_name":"Graph","score":0.5818793177604675},{"id":"https://openalex.org/keywords/extension","display_name":"Extension (predicate logic)","score":0.5394251346588135},{"id":"https://openalex.org/keywords/theoretical-computer-science","display_name":"Theoretical computer science","score":0.5286850333213806},{"id":"https://openalex.org/keywords/programming-language","display_name":"Programming language","score":0.4917488396167755},{"id":"https://openalex.org/keywords/graph-database","display_name":"Graph database","score":0.43801483511924744},{"id":"https://openalex.org/keywords/relational-database","display_name":"Relational database","score":0.4244052469730377},{"id":"https://openalex.org/keywords/database","display_name":"Database","score":0.3220025599002838}],"concepts":[{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.894889235496521},{"id":"https://openalex.org/C510870499","wikidata":"https://www.wikidata.org/wiki/Q47607","display_name":"SQL","level":2,"score":0.7436736822128296},{"id":"https://openalex.org/C195818886","wikidata":"https://www.wikidata.org/wiki/Q5421724","display_name":"Expressive power","level":2,"score":0.6218501925468445},{"id":"https://openalex.org/C132525143","wikidata":"https://www.wikidata.org/wiki/Q141488","display_name":"Graph","level":2,"score":0.5818793177604675},{"id":"https://openalex.org/C2778029271","wikidata":"https://www.wikidata.org/wiki/Q5421931","display_name":"Extension (predicate logic)","level":2,"score":0.5394251346588135},{"id":"https://openalex.org/C80444323","wikidata":"https://www.wikidata.org/wiki/Q2878974","display_name":"Theoretical computer science","level":1,"score":0.5286850333213806},{"id":"https://openalex.org/C199360897","wikidata":"https://www.wikidata.org/wiki/Q9143","display_name":"Programming language","level":1,"score":0.4917488396167755},{"id":"https://openalex.org/C176225458","wikidata":"https://www.wikidata.org/wiki/Q595971","display_name":"Graph database","level":3,"score":0.43801483511924744},{"id":"https://openalex.org/C5655090","wikidata":"https://www.wikidata.org/wiki/Q192588","display_name":"Relational database","level":2,"score":0.4244052469730377},{"id":"https://openalex.org/C77088390","wikidata":"https://www.wikidata.org/wiki/Q8513","display_name":"Database","level":1,"score":0.3220025599002838}],"mesh":[],"locations_count":1,"locations":[{"id":"doi:10.1016/0096-0551(90)90011-d","is_oa":false,"landing_page_url":"https://doi.org/10.1016/0096-0551(90)90011-d","pdf_url":null,"source":{"id":"https://openalex.org/S181974911","display_name":"Computer Languages","issn_l":"0096-0551","issn":["0096-0551","1873-6742"],"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":"Computer Languages","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":31,"referenced_works":["https://openalex.org/W74021744","https://openalex.org/W1544789779","https://openalex.org/W1554224014","https://openalex.org/W1607154789","https://openalex.org/W1984890936","https://openalex.org/W2013951929","https://openalex.org/W2054633003","https://openalex.org/W2075209053","https://openalex.org/W2088094394","https://openalex.org/W2089692469","https://openalex.org/W2105775150","https://openalex.org/W2125362004","https://openalex.org/W2132063146","https://openalex.org/W2150111014","https://openalex.org/W2161609549","https://openalex.org/W2165467455","https://openalex.org/W2185907055","https://openalex.org/W2914795306","https://openalex.org/W4249958171","https://openalex.org/W4300354056","https://openalex.org/W6603010099","https://openalex.org/W6631393269","https://openalex.org/W6632877052","https://openalex.org/W6633153615","https://openalex.org/W6654115460","https://openalex.org/W6669483523","https://openalex.org/W6672579723","https://openalex.org/W6672763640","https://openalex.org/W6675850408","https://openalex.org/W6679362585","https://openalex.org/W6682089088"],"related_works":["https://openalex.org/W2573939812","https://openalex.org/W2120098008","https://openalex.org/W2898886863","https://openalex.org/W1639806124","https://openalex.org/W2902831276","https://openalex.org/W2165259096","https://openalex.org/W2540682188","https://openalex.org/W4385834214","https://openalex.org/W3022423983","https://openalex.org/W12347151"],"abstract_inverted_index":null,"counts_by_year":[],"updated_date":"2026-06-11T09:08:48.828518","created_date":"2025-10-10T00:00:00"}
