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A Database Querying Language for Formulating Relational Queries on Small Devices
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作者 Ahmad Rohiza Abdul-Kareem Sameem 《Computer Technology and Application》 2011年第3期172-181,共10页
For small devices like the PDAs and mobile phones, formulation of relational database queries is not as simple as using conventional devices such as the personal computers and laptops. Due to the restricted size and r... For small devices like the PDAs and mobile phones, formulation of relational database queries is not as simple as using conventional devices such as the personal computers and laptops. Due to the restricted size and resources of these smaller devices, current works mostly limit the queries that can be posed by users by having them predetermined by the developers. This limits the capability of these devices in supporting robust queries. Hence, this paper proposes a universal relation based database querying language which is targeted for small devices. The language allows formulation of relational database queries that uses minimal query terms. The formulation of the language and its structure will be described and usability test results will be presented to support the effectiveness of the language. 展开更多
关键词 databasE query language relational queries small devices.
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A solution of spatial query processing and query optimization for spatial databases
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作者 YUANJie XIEKun-qing +2 位作者 MAXiu-jun ZHANGMin SUNLe-bin 《重庆邮电学院学报(自然科学版)》 2004年第5期165-172,共8页
Recently, attention has been focused on spatial query language which is used to query spatial databases. A design of spatial query language has been presented in this paper by extending the standard relational databas... Recently, attention has been focused on spatial query language which is used to query spatial databases. A design of spatial query language has been presented in this paper by extending the standard relational database query language SQL. It recognizes the significantly different requirements of spatial data handling and overcomes the inherent problems of the application of conventional database query languages. This design is based on an extended spatial data model, including the spatial data types and the spatial operators on them. The processing and optimization of spatial queries have also been discussed in this design. In the end, an implementation of this design is given in a spatial query subsystem. 展开更多
关键词 空间数据库 询问语言 空间数据模型 空间操作 最优化
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Query Languages for Temporal Database
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作者 邓培民 《High Technology Letters》 EI CAS 1997年第2期47-51,共5页
In this paper, an interval-gap-based 1NF temporal tuple calculus language and the corresponding temporal relation algebra are established on the basis of considering the trouble of stack operations in both S. Gadia’s... In this paper, an interval-gap-based 1NF temporal tuple calculus language and the corresponding temporal relation algebra are established on the basis of considering the trouble of stack operations in both S. Gadia’s TCAL and temporal tuple calculus due to their NINF. 展开更多
关键词 TEMPORAL database SQL TEMPORAL relatION ALGEBRA TUPLE CALCULUS query language
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PORLES:A Parallel Object Relational Database System
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作者 Sun Yong\|qiang, Xu Shu\|ting, Zhu Feng\|hua, Lai Shu\|huaDepartment of Computer Science and Engineering, Shanghai Jiaotong University, Shanghai 200030,China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期100-109,共10页
We developed a parallel object relational DBMS named PORLES. It uses BSP model as its parallel computing model, and monoid calculus as its basis of data model. In this paper, we introduce its data model, parallel que... We developed a parallel object relational DBMS named PORLES. It uses BSP model as its parallel computing model, and monoid calculus as its basis of data model. In this paper, we introduce its data model, parallel query optimization, transaction processing system and parallel access method in detail. 展开更多
关键词 parallel object relational database BSP model data model query optimization
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A Shallow Parsing Approach to Natural Language Queries of a Database
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作者 Richard Skeggs Stasha Lauria 《Journal of Software Engineering and Applications》 2019年第9期365-382,共18页
The performance and reliability of converting natural language into structured query language can be problematic in handling nuances that are prevalent in natural language. Relational databases are not designed to und... The performance and reliability of converting natural language into structured query language can be problematic in handling nuances that are prevalent in natural language. Relational databases are not designed to understand language nuance, therefore the question why we must handle nuance has to be asked. This paper is looking at an alternative solution for the conversion of a Natural Language Query into a Structured Query Language (SQL) capable of being used to search a relational database. The process uses the natural language concept, Part of Speech to identify words that can be used to identify database tables and table columns. The use of Open NLP based grammar files, as well as additional configuration files, assist in the translation from natural language to query language. Having identified which tables and which columns contain the pertinent data the next step is to create the SQL statement. 展开更多
关键词 NLIDB NATURAL languagE Processing databasE query Data MINING
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Large Language Model Based Semantic Parsing for Intelligent Database Query Engine
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作者 Zhizhong Wu 《Journal of Computer and Communications》 2024年第10期1-13,共13页
With the rapid development of artificial intelligence, large language models (LLMs) have demonstrated remarkable capabilities in natural language understanding and generation. These models have great potential to enha... With the rapid development of artificial intelligence, large language models (LLMs) have demonstrated remarkable capabilities in natural language understanding and generation. These models have great potential to enhance database query systems, enabling more intuitive and semantic query mechanisms. Our model leverages LLM’s deep learning architecture to interpret and process natural language queries and translate them into accurate database queries. The system integrates an LLM-powered semantic parser that translates user input into structured queries that can be understood by the database management system. First, the user query is pre-processed, the text is normalized, and the ambiguity is removed. This is followed by semantic parsing, where the LLM interprets the pre-processed text and identifies key entities and relationships. This is followed by query generation, which converts the parsed information into a structured query format and tailors it to the target database schema. Finally, there is query execution and feedback, where the resulting query is executed on the database and the results are returned to the user. The system also provides feedback mechanisms to improve and optimize future query interpretations. By using advanced LLMs for model implementation and fine-tuning on diverse datasets, the experimental results show that the proposed method significantly improves the accuracy and usability of database queries, making data retrieval easy for users without specialized knowledge. 展开更多
关键词 Semantic query Large language Models Intelligent database Natural language Processing
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Semantic-based query processing for relational data integration 被引量:1
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作者 苗壮 张亚非 +2 位作者 王进鹏 陆建江 周波 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期22-25,共4页
To solve the query processing correctness problem for semantic-based relational data integration,the semantics of SAPRQL(simple protocol and RDF query language) queries is defined.In the course of query rewriting,al... To solve the query processing correctness problem for semantic-based relational data integration,the semantics of SAPRQL(simple protocol and RDF query language) queries is defined.In the course of query rewriting,all relative tables are found and decomposed into minimal connectable units.Minimal connectable units are joined according to semantic queries to produce the semantically correct query plans.Algorithms for query rewriting and transforming are presented.Computational complexity of the algorithms is discussed.Under the worst case,the query decomposing algorithm can be finished in O(n2) time and the query rewriting algorithm requires O(nm) time.And the performance of the algorithms is verified by experiments,and experimental results show that when the length of query is less than 8,the query processing algorithms can provide satisfactory performance. 展开更多
关键词 data integration relational database simple protocol and RDF query language(SPARQL) minimal connectable unit query processing
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Query Optimization for Deductive Databases
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作者 周傲英 施伯乐 《Journal of Computer Science & Technology》 SCIE EI CSCD 1995年第2期134-148,共15页
A systematic, efficient compilation method for query evaluation of DeductiveDatabases (DeDB) is proposed in this paper. In order to eliminate redundancyand to minimize the potentially relevant facts, which are two key... A systematic, efficient compilation method for query evaluation of DeductiveDatabases (DeDB) is proposed in this paper. In order to eliminate redundancyand to minimize the potentially relevant facts, which are two key issues to theefficiency of a DeDB, the compilation process is decomposed into two phases.The first is the pre-compilation phase, which is responsible for the minimiza-tion of the potentially relevant facts. The second, which we refer to as thegeneral compilation phase, is responsible for the elimination of redundancy.The rule/goal graph devised by J. D. Ullman is appropriately extended andused as a uniform formalism. Two general algorithms corresponding to the twophases respectively are described intuitively and formally 展开更多
关键词 deductive database query evaluation query optimization
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An Efficient Algorithm for Processing Multi-Relation Queries in Relational Databases
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作者 刘惟一 《Journal of Computer Science & Technology》 SCIE EI CSCD 1990年第3期236-240,共5页
After a relation scheme R is decomposed into the set of schemes ρ={R_1,...,R_n},we may pose queries as if R existed in the database,taking a join of R_i's,when it is necessary to implement the query.Suppose a que... After a relation scheme R is decomposed into the set of schemes ρ={R_1,...,R_n},we may pose queries as if R existed in the database,taking a join of R_i's,when it is necessary to implement the query.Suppose a query involves a set of attributes S(?)R,we want to find the smallest subset of ρ whose union includes S.We prove that the problem is NP-complete and present a polynomial-bounded approximation algorithm.A subset of ρ whose union includes S and has a decomposition into 3NF with a lossless join and preservation of dependencies is given in the paper. 展开更多
关键词 Pro An Efficient Algorithm for Processing Multi-relation Queries in relational databases
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A New Database Intrusion Detection Approach Based on Hybrid Meta-Heuristics 被引量:9
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作者 Youseef Alotaibi 《Computers, Materials & Continua》 SCIE EI 2021年第2期1879-1895,共17页
A new secured database management system architecture using intrusion detection systems(IDS)is proposed in this paper for organizations with no previous role mapping for users.A simple representation of Structured Que... A new secured database management system architecture using intrusion detection systems(IDS)is proposed in this paper for organizations with no previous role mapping for users.A simple representation of Structured Query Language queries is proposed to easily permit the use of the worked clustering algorithm.A new clustering algorithm that uses a tube search with adaptive memory is applied to database log files to create users’profiles.Then,queries issued for each user are checked against the related user profile using a classifier to determine whether or not each query is malicious.The IDS will stop query execution or report the threat to the responsible person if the query is malicious.A simple classifier based on the Euclidean distance is used and the issued query is transformed to the proposed simple representation using a classifier,where the Euclidean distance between the centers and the profile’s issued query is calculated.A synthetic data set is used for our experimental evaluations.Normal user access behavior in relation to the database is modelled using the data set.The false negative(FN)and false positive(FP)rates are used to compare our proposed algorithm with other methods.The experimental results indicate that our proposed method results in very small FN and FP rates. 展开更多
关键词 Adaptive search memory clustering database management system(DBMS) intrusion detection system(IDS) quiplets structured query language(SQL) tube search
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Evaluating Relational Ranking Queries Involving both Text Attributes and Numeric Attributes
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作者 Liang Zhu Zhaoliang Xie Qin Ma 《Journal of Software Engineering and Applications》 2012年第12期88-93,共6页
In many database applications, ranking queries may reference both text and numeric attributes, where the ranking functions are based on both semantic distances/similarities for text attributes and numeric distances fo... In many database applications, ranking queries may reference both text and numeric attributes, where the ranking functions are based on both semantic distances/similarities for text attributes and numeric distances for numeric attributes. In this paper, we propose a new method for evaluating such type of ranking queries over a relational database. By statistics and training, this method builds a mechanism that combines the semantic and numeric distances, and the mechanism can be used to balance the effects of text attributes and numeric attributes on matching a given query and tuples in database search. The basic idea of the method is to create an index based on WordNet to expand the tuple words semantically for text attributes and on the information of numeric attributes. The candidate results for a query are retrieved by the index and a simple SQL selection statement, and then top-N answers are obtained. The results of extensive experiments indicate that the performance of this new strategy is efficient and effective. 展开更多
关键词 relational database RANKING query Semantic DISTANCE Numeric DISTANCE WORDNET
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Research on Substation Equipment Configuration Based on Object-Oriented Database
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作者 Yu Song Dandan Li 《通讯和计算机(中英文版)》 2011年第8期615-618,共4页
关键词 面向对象数据库 变电站 设备配置 可扩展标记语言 智能电子设备 关系型数据库 关系数据库 配置过程
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CLASCN: Candidate Network Selection for Efficient Top-κ Keyword Queries over Databases 被引量:2
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作者 张俊 彭朝晖 +1 位作者 王珊 聂惠静 《Journal of Computer Science & Technology》 SCIE EI CSCD 2007年第2期197-207,共11页
Keyword Search Over Relational Databases (KSORD) enables casual or Web users easily access databases through free-form keyword queries. Improving the performance of KSORD systems is a critical issue in this area. In... Keyword Search Over Relational Databases (KSORD) enables casual or Web users easily access databases through free-form keyword queries. Improving the performance of KSORD systems is a critical issue in this area. In this paper, a new approach CLASCN (Classification, Learning And Selection of Candidate Network) is developed to efficiently perform top-κ keyword queries in schema-graph-based online KSORD systems. In this approach, the Candidate Networks (CNs) from trained keyword queries or executed user queries are classified and stored in the databases, and top-κ results from the CNs are learned for constructing CN Language Models (CNLMs). The CNLMs are used to compute the similarity scores between a new user query and the CNs from the query. The CNs with relatively large similarity score, which are the most promising ones to produce top-κ results, will be selected and performed. Currently, CLASCN is only applicable for past queries and New All-keyword-Used (NAU) queries which are frequently submitted queries. Extensive experiments also show the efficiency and effectiveness of our CLASCN approach. 展开更多
关键词 relational database keyword search top-κ query candidate network
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面向营商环境评估的异构融合存储区块链查询优化方法
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作者 李素 王俊陆 +2 位作者 陈泽 王妍 宋宝燕 《计算机科学与探索》 北大核心 2026年第3期892-904,共13页
营商环境的优劣对现代化经济高质量可持续发展具有重要战略意义。为有效提升营商环境评估的可信度与执行效能,针对现有营商区块链系统中存在的存储资源消耗过高、查询接口功能单一、可支持查询模式受限等问题,创新性地提出一种异构融合... 营商环境的优劣对现代化经济高质量可持续发展具有重要战略意义。为有效提升营商环境评估的可信度与执行效能,针对现有营商区块链系统中存在的存储资源消耗过高、查询接口功能单一、可支持查询模式受限等问题,创新性地提出一种异构融合存储区块链查询优化方法。基于营商环境区块链数据多源高维的特性,设计一种链上-链下协同的异构融合存储架构,降低整体存储开销,并为区块数据添加关系语义,实现数据关系语义增强,以支持复杂查询;构建索引机制(包含区块索引、表级位图索引、层次索引),以加速营商环境评估进行数据查询时的访问效率,丰富查询类型;根据不同索引结构的特性适配最佳营商环境评估查询场景,设计三种动态自适应查询优化算法,进一步优化了查询效率。在四类公开数据集上的实验表明,所提方法在保证可用性的前提下,显著降低了存储开销,对三种不同的查询类型具有较短的查询延迟,相较于基线方法,整体性能也有显著提升。 展开更多
关键词 区块链数据库 数据存储 关系语义 索引 查询优化
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基于大语言模型的数据库设计实验课教学探索
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作者 乔少杰 李薇 +5 位作者 徐倩 王星捷 韩楠 王晓玲 唐婷婷 陈权亮 《实验室科学》 2026年第1期3-9,共7页
大语言模型(large language model,LLM)为数据库性能带来了极大的提升,将LLM与数据库相结合成为当前的研究热点。然而,目前大部分高校数据库实验课程仍停留于数据库基础操作层面,学生普遍缺乏数据库前沿技术相关知识。文本转结构化查询... 大语言模型(large language model,LLM)为数据库性能带来了极大的提升,将LLM与数据库相结合成为当前的研究热点。然而,目前大部分高校数据库实验课程仍停留于数据库基础操作层面,学生普遍缺乏数据库前沿技术相关知识。文本转结构化查询语言(text to structured query language,Text-to-SQL)技术为基于LLM的数据库设计的重要研究方向之一。首先,设计实验课程系统地介绍基于LLM的Text-to-SQL方法的教学意义,以盘古大模型为例对实验课程相关技术进行介绍;其次,分析并划定基于LLM的数据库设计实验课程的教学目标,阐述具体的教学设计和实施;最后,对教学方法设计的各方面进行系统总结。 展开更多
关键词 大语言模型 Text-to-SQL 实验课教学 数据库设计 盘古大模型
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Processing and optimization of UMQL-based multimedia queries
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作者 吴宗大 曹忠升 +1 位作者 王元珍 李桂玲 《Journal of Southeast University(English Edition)》 EI CAS 2009年第3期320-325,共6页
Through the mapping from UMQL ( unified multimedia query language) conditional expressions to UMQA (unified multimedia query algebra) query operations, a translation algorithm from a UMQL query to a UMQA query pla... Through the mapping from UMQL ( unified multimedia query language) conditional expressions to UMQA (unified multimedia query algebra) query operations, a translation algorithm from a UMQL query to a UMQA query plan is put forward, which can generate an equivalent UMQA internal query plan for any UMQL query. Then, to improve the execution costs of UMQA query plans effectively, equivalent UMQA translation formulae and general optimization strategies are studied, and an optimization algorithm for UMQA internal query plans is presented. This algorithm uses equivalent UMQA translation formulae to optimize query plans, and makes the optimized query plans accord with the optimization strategies as much as possible. Finally, the logic implementation methods of UMQA plans, i.e., logic implementation methods of UMQA operators, are discussed to obtain useful target data from a muifirnedia database. All of these algorithms are implemented in a UMQL prototype system. Application results show that these query processing techniques are feasible and applicable. 展开更多
关键词 multimedia database multimedia query language query optimization unified multimedia query language
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FIRST ORDER LANGUAGE FOR ENTITY-ROLES MODEL^+
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作者 Pan Jiuhui Liu Zhimin Wang Yunyi(Department of Computer Science, Central South University of Technology. Changsha, 410083. China) 《Journal of Central South University》 SCIE EI CAS 1995年第1期59-63,共5页
With respect to the mathematical structure supposed by theEntity-Roles Model. a first order (three--valued) logic language is constructured. A world to be modelled can be logically specified in this language. The inte... With respect to the mathematical structure supposed by theEntity-Roles Model. a first order (three--valued) logic language is constructured. A world to be modelled can be logically specified in this language. The integrity constraints on the database and 展开更多
关键词 knowledge/data model EXPERT databasE OBJECT-ORIENTATION databasE logic deductive query
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基于大模型检索增强生成的气象数据库问答模型实现 被引量:12
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作者 江双五 张嘉玮 +1 位作者 华连生 杨菁林 《计算机工程与应用》 北大核心 2025年第5期113-121,共9页
随着信息检索和知识获取需求的增加,智能问答系统在多个垂直领域得到广泛应用。然而,在气象领域仍缺乏专门的智能问答系统研究,严重限制了气象信息的高效利用和气象系统的服务效率。针对这一需求,提出了一种面向气象数据库的大模型检索... 随着信息检索和知识获取需求的增加,智能问答系统在多个垂直领域得到广泛应用。然而,在气象领域仍缺乏专门的智能问答系统研究,严重限制了气象信息的高效利用和气象系统的服务效率。针对这一需求,提出了一种面向气象数据库的大模型检索智能问答技术实现方案。该方案设计了一种基于关系型数据库(SQL)与文档型数据(NoSQL)的多通道查询路由(multi-channel retrieval router,McRR)方法,为了适配数据库进行大模型查询以及增强大模型对查询表的理解,分别提出指令查询转换方法与数据库表摘要方法DNSUM,提升大模型对数据库的语义理解能力,通过结合问题理解、重排序器和响应生成等关键模块,构建了一个端到端的智能问答模型,可实现多数据源的相关知识检索及答案生成。实验结果显示,该模型可以有效理解用户问题并生成准确的答案,具有良好的检索和响应能力。不仅为气象领域提供了一种智能问答的解决方案,也为气象智能问答技术提供了新的应用实施参考。 展开更多
关键词 数据库查询 数据库问答 大语言模型 检索增强生成 气象问答
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Dealing with Empty and Overabundant Answers to Flexible Queries
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作者 Samyr Abrahao Moises Silvio do Lago Pereira 《Journal of Data Analysis and Information Processing》 2014年第1期12-18,共7页
In traditional database applications, queries intend to retrieve data satisfying precise conditions. As a result, thousands of data can be retrieved (overabundant answer) or, even worse, no data at all (empty answer).... In traditional database applications, queries intend to retrieve data satisfying precise conditions. As a result, thousands of data can be retrieved (overabundant answer) or, even worse, no data at all (empty answer). In both cases, the queries must be reformulated to produce more significant results and, typically, many related queries are submitted by a user before he can be finally satisfied. To overcome these problems, this paper proposes a unified solution in the framework of flexible queries with fuzzy semantics. This solution, based on the concept of semantic proximity and implemented in a tool for flexible query answering, allows the automatic reformulation of queries with empty or overabundant answers. 展开更多
关键词 relational database Fuzzy Logic Flexible query Empty Answer Overabundant Answer
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因素查询语言(FQL)-因素数据库的基本语言
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作者 孟祥福 李子函 +4 位作者 史家晟 郭建威 赵亮 郭嗣琮 汪培庄 《计算机科学》 北大核心 2025年第S1期651-658,共8页
为支持因素空间理论背景下因素谱系数据的基本存储与高效处理,提出了一种因素查询语言(Factor Query Language,FQL)和因素库管理系统(FBMS)架构。首先,介绍因素谱系的相关概念并给出基于XML规范的因素谱系存储方法。然后,设计因素查询... 为支持因素空间理论背景下因素谱系数据的基本存储与高效处理,提出了一种因素查询语言(Factor Query Language,FQL)和因素库管理系统(FBMS)架构。首先,介绍因素谱系的相关概念并给出基于XML规范的因素谱系存储方法。然后,设计因素查询语言的增删改查基本操作规范。为提高因素的查询效率,在提高数据更新速度的同时降低索引更新成本,针对因素谱系特点进一步提出了基于区间和基于素数与二进制串的因素编码策略。最后,对因素库管理系统的系统架构和功能模块进行了相应设计,作为因素查询语言的操作载体。因素查询语言FQL和因素库管理系统,是因素空间理论落地实施的系统平台,文章在该方面进行了初步探讨,为因素库管理系统的研发和应用提供了基本思路和解决方案。 展开更多
关键词 因素空间 因素库 因素谱系 因素查询语言 因素编码 因素库管理系统
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