{"title":"Limiting a resolution set in a large Prolog database using special hardware","authors":"Kam-Fai Wong, M. H. Williams","doi":"10.1145/62453.62484","DOIUrl":null,"url":null,"abstract":"There is a growing interest in the application of Prolog and related languages like Parlog to database implementation. Existing Prolog systems, however, are unable to cope with large sets of data of the size necessary for databases. A large Prolog database would consist of millions of clauses. The size of physical memory required to store the database has deemed main memory impractical in many computer systems. Therefore clauses are usually placed on secondary disc memory. Clause retrieval, however, becomes extremely slow. Furthermore, the enormous amount of time required for unification upon a large set of clauses has drastically degraded system performance. Either of these factors leads to non-timely database response which is irritating and in many cases, intolerable. To mediate these problems, a special hardware unit is proposed - the CLAuse Retrieval Engine (CLARE). The functions of the CLARE are to search discs storing database clauses on-the-fly and select potentially unifiable clauses. Two stages of filtering will be applied to the database clauses; thus a small resolution set will be guaranteed.","PeriodicalId":147067,"journal":{"name":"Symposium on Small Systems","volume":"6 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"1988-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"2","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Symposium on Small Systems","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1145/62453.62484","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 2
Abstract
There is a growing interest in the application of Prolog and related languages like Parlog to database implementation. Existing Prolog systems, however, are unable to cope with large sets of data of the size necessary for databases. A large Prolog database would consist of millions of clauses. The size of physical memory required to store the database has deemed main memory impractical in many computer systems. Therefore clauses are usually placed on secondary disc memory. Clause retrieval, however, becomes extremely slow. Furthermore, the enormous amount of time required for unification upon a large set of clauses has drastically degraded system performance. Either of these factors leads to non-timely database response which is irritating and in many cases, intolerable. To mediate these problems, a special hardware unit is proposed - the CLAuse Retrieval Engine (CLARE). The functions of the CLARE are to search discs storing database clauses on-the-fly and select potentially unifiable clauses. Two stages of filtering will be applied to the database clauses; thus a small resolution set will be guaranteed.