基于Oracle的音像租赁管理系统数据库设计

给出了小型音像租赁店的业务需求、信息需求和业务规则,用Oracle数据库设计的思想分析了本系统中的实体和关系,进行了数据库概念模型设计,并用ERD图表进行数据库设计,给出了数据库逻辑设计结果。     

数据库设计工具集DBTOOLS的设计

本文介绍的数据库设计工具集DBTOOLS包括扩充的E—R模型设计工具EERD、从E—R模型到关系模型转换工具ERTR、从DFD、DD到关系模型转换工具DDTR,DBTOOLS以自动转换和人工干预相结合的方式工作,提供对关系数据库概念结构设计和逻辑结构设计的支持,DBTOOLS的设计中强调语义信息的描述和运用,以及对数据库应用系统增量开发的支持。     

Using an entity model to drive physical database design

Logical relational database design, because of its implementation-independent nature, has been successfully formalized. Physical relational database design, because of its implementation-dependent nature, has remained largely unformalized and disconnected, not only from logical design but also from conceptual database design. The paper suggests a model for the physical design process that has proven useful in a number of practical development projects. The model demonstrates that a seamless join between conceptual, logical and physical design work is feasible. It illustrates how the process of annotating a conceptual model with physical detail provides a useful framework for driving the process of physical relational database design.     

A survey of database design transformations based on the Entity-Relationship model

At present, the Entity-Relationship (ER) model is the most important paradigm for conceptual database design. Since the model was introduced in the mid-seventies, a large body of literature has been published on transforming conceptual ER schemas or diagrams into logical data models. The purpose of this paper is to survey this literature. A first focus is on transformation approaches from the ER model to traditional data models, i.e. to the relational, the network, or the hierarchical model; this is then complemented by a discussion of more recent transformations to object-oriented models. A second focus is on considering the process of reverse engineering, i.e. transformations from a logical model back into the ER model; finally, an overview of direct transformations between various logical data models is presented.     

Modeling and Management of Fuzzy Information in Multimedia Database Applications

In this paper, we firstly present a conceptual data model for multimedia database applications based on ExIFO₂ model. The ExIFO₂ data model is chosen as the conceptual model since it handles complex objects along with their uncertain and imprecise properties. We enhanced this conceptual model in order to meet the multimedia data requirements. In addition to uncertain and imprecise information, we present a way of handling relationships among objects of multimedia database applications. Events that might be extracted from video or audio are also considered in this study. Secondly, the conceptual model is mapped to a logical model, which the fuzzy object-oriented data (FOOD) model is chosen, for storing and manipulating the multimedia objects. This mapping is done in a way that it preserves most of the information represented at the conceptual level. Finally, in this study videos of football (soccer) games is selected as the multimedia database application to show how we handle crisp and fuzzy querying and retrieval of fuzzy and crisp data from the database. A program has been developed to draw ExIFO₂ schemas and to map the schema to FOOD code automatically.     

Towards a new approach to secure database design

The problem of designing and managing a secure database system is considered in this paper. The approach which is proposed is primarily concerned with the security information definition and management in a database environment. A multiphase design methodology is presented reflecting current proposals of database design methodology. In particular four design phases are proposed: requirements analysis of the security system, conceptual, logical and physical design of security information. The content and the solution techniques of each phase are examined. A database management system architecture is also presented which is suitable to control access rights to the database.     

Designing secure databases

Security is an important issue that must be considered as a fundamental requirement in information systems development, and particularly in database design. Therefore security, as a further quality property of software, must be tackled at all stages of the development. The most extended secure database model is the multilevel model, which permits the classification of information according to its confidentiality, and considers mandatory access control. Nevertheless, the problem is that no database design methodologies that consider security (and therefore secure database models) across the entire life cycle, particularly at the earliest stages currently exist. Therefore it is not possible to design secure databases appropriately. Our aim is to solve this problem by proposing a methodology for the design of secure databases. In addition to this methodology, we have defined some models that allow us to include security information in the database model, and a constraint language to define security constraints. As a result, we can specify a fine-grained classification of the information, defining with a high degree of accuracy which properties each user has to own in order to be able to access each piece of information. The methodology consists of four stages: requirements gathering; database analysis; multilevel relational logical design; and specific logical design. The first three stages define activities to analyze and design a secure database, thus producing a general secure database model. The last stage is made up of activities that adapt the general secure data model to one of the most popular secure database management systems: Oracle9i Label Security. This methodology has been used in a genuine case by the Data Processing Center of Provincial Government. In order to support the methodology, we have implemented an extension of Rational Rose, including and managing security information and constraints in the first stages of the methodology.     

A conceptual database design approach based on rules and heuristics

Conceptual and logical database design are complex tasks for non-expert designers. Currently, the popular data models for conceptual and logical database design are the entity–relationship (ER) and the relational model, respectively. Logical design methodologies for relational databases have relied on mathematically rigorous approaches which are impractical, or textbook approaches which do not provide the rich constructs to capture real applications. Consequently, designers have to use their intuition to develop their own rules and heuristics. There is a need, therefore, to develop practical rules and heuristics that can be used to handle the complexity of design in real applications. This paper proposes a realistic and detailed approach for conceptual design using the ER model for relational databases. The approach is based on four rules that specify the order in which various types of relationships must be modelled, three rules that pertain to detection of derived relationships, and three heuristics based on observation of constructs in real applications. The approach is illustrated by many examples.     

A new programming paradigm for engineering design software

Currently available programming and database systems are insufficient for engineering applications. The authors contend that a logical progression from a formal conceptual model of the engineering domain to a computational model will lead to new programming paradigms capable of directly supporting engineering applications in a rigorous, concise manner. A formal domain model devised by the authors, theHybrid Model (HM) of design information, is briefly introduced. It is an extension of axiomatic set theory and is discussed in detail elsewhere. HM forms the basis ofDesigner, a prototype-based object-oriented programming language supporting a signature-based canonical message-passing mechanism and multiple inheritance. Designer is implemented using the Scheme programming language. Because Designer satisfies a formal conceptual model, and because it is based on a formally specified language, its robustness and logical validity are superior to those of other languages not founded on formal principles. Designer combines concepts of functional and object-oriented programming to provide the formal rigor and flexibility to capture the complex and strongly interrelated information that designers use. Examples demonstrate how Designer represents design information. The results of the authors' research indicate that Designer can capture design information (including aspects of functional requirements and design intent) effectively and efficiently.     

数据库设计中的主观过程讨论

数据库设计具有实践性强、主观性高及过程不断反复的特点,对初学者是一个难点。数据库设计的主观过程主要涉及到概念模型设计和逻辑模型优化两个环节,文章以案例的形式阐述了数据库设计的特点以及设计过程中的一般原则。     

ADDS: A system for automatic database schema design based on the binary-relationship model

This paper presents the system ADDS that has been developed to assist the database designer designing a database schema. A distinction is made between the stage of information structure analysis in which the information structure of the system is defined according to its user information needs, and the stage of database schema design in which the record types of the database and the relationships between them are defined. In the first stage a conceptual schema is obtained, represented as an information structure diagram (ISD), and in the later stage the ISD is used to derive the database schema in the form of a data structure diagram (DSD).ADDS automatically creates the database schema out of a conceptual schema which is expressed as an ISD of the binary-relationship data mode. The resulting schema consists of normalized record types, according to the relation model, along with hierarchical/set relationships between ‘owner’ and ‘member’ record types, as in the CODASYL/Network model. ADDS applies algorithms to convert the conceptual schema into the database schema. It is implemented on a micro-computer under MS-DOS using dBASE III.     

CAD^2B—一个计算机辅助数据库设计系统

本文介绍了一个用Ｔｕｒｂｏ Ｃ语言在ＡＳＴ－２８６机器上实现的计算机辅助数据库设计系统ＣＡＤ＾２Ｂ。该系统提供了人机交互的环境，供设计者进行概念模型设计，并自动完成从概念模型逻辑模型的映射，创建满足规范化要求的关系表。该系统采用的概念模型是引入了事件和时间的扩展了的实体关系模型。该模型既能充分反映应用环境的静态和动态语义，又是向关系模式转化的基础。     

人才信息系统数据库设计

在人才信息系统的功能需求基础上,设计了一个信息数据库,能够实现招聘信息发布与查找、应聘信息发布与查找以及人才信息统计等功能。整个设计过程从需求分析、概念设计、逻辑设计等方面进行探讨。     

分布式数据库设计中数据和操作的分配

提出了将全局关系分段,将查询和更新操作分解成这些分段上的关系操作步,然后用系统费用摸型将分段和操作分配到各站点以使系统费用最小,从而建立分布式数据库设计模型。     

A conceptual schema-based temporal meta database schemas generation technique for 3D objects

In this paper, a temporal meta database for three-dimensional (3D) objects whose properties and relationships are supported by valid time is introduced. Based on our proposed temporal object-oriented conceptual schema model, a conceptual schema of the temporal meta database can be generated from a 3D graphical data source and other particular application requirements. Based on our proposed temporal object relational data model with attribute timestamping, logical schemas of the temporal meta database can be systematically and automatically generated from the conceptual schema. From the temporal meta database, non-temporal/temporal metadata about temporal 3D objects are available for temporal information system users. Convenient access using database languages such as SQL can be performed. Queries over 3D objects using a temporal object relational SQL are demonstrated.     

Information system analysis and conceptual database design in production environments with M1

A methodology, called M¹, for information system analysis and database design of production environments is presented in detail. The originality of M¹ is to recognize the importance of integrating factory analysis methods for data and user requirements definition with logical database design methods for database specification. M¹ is a pragmatic, complete, manual methodology involving three major phases: Enterprise Modelling and Analysis which is the phase devoted to accurate analysis of the structure of the enterprise and precise definition of the scope of the future database application; Conceptual Design which is the phase concerned with data modelling of both static and dynamic properties of the enterprise; and Implementation Design which is the phase dealing with adaptation of the conceptual schema to the data model specifications of the physical database system used for application development and tuning performances of the physical system. The methodology is explained and illustrated by means of an example related to a Flexible Manufacturing System for mechanical parts.