{"title":"有,一个关系代数运算符或除法不足以征服","authors":"J. Carlis","doi":"10.1109/ICDE.1986.7266229","DOIUrl":null,"url":null,"abstract":"The relational algebra operator division is misnamed, hard to understand and insufficient. This paper explains division and presents HAS, a generalization of division which is useful for answering questions about an M-M relationship between entities.","PeriodicalId":415748,"journal":{"name":"1986 IEEE Second International Conference on Data Engineering","volume":"83 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"1986-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"22","resultStr":"{\"title\":\"HAS, a relational algebra operator or divide is not enough to conquer\",\"authors\":\"J. Carlis\",\"doi\":\"10.1109/ICDE.1986.7266229\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"The relational algebra operator division is misnamed, hard to understand and insufficient. This paper explains division and presents HAS, a generalization of division which is useful for answering questions about an M-M relationship between entities.\",\"PeriodicalId\":415748,\"journal\":{\"name\":\"1986 IEEE Second International Conference on Data Engineering\",\"volume\":\"83 1\",\"pages\":\"0\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"1986-02-05\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"22\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"1986 IEEE Second International Conference on Data Engineering\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1109/ICDE.1986.7266229\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"1986 IEEE Second International Conference on Data Engineering","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/ICDE.1986.7266229","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
HAS, a relational algebra operator or divide is not enough to conquer
The relational algebra operator division is misnamed, hard to understand and insufficient. This paper explains division and presents HAS, a generalization of division which is useful for answering questions about an M-M relationship between entities.