Abstract class: A class that has no direct instances, but whose descendants may have direct instances. (20) See also Concrete class.
Abstract operation: Defines the form or protocol of the operation, but not its implementation. (20) See also Operation.
Acceptance testing: The process whereby actual users test a completed information system, the end result of which is the users' acceptance of it. (17) See also System testing.
Action stubs: That part of a decision table that lists the actions that result for a given set of conditions. (9)
Activation: The time period during which an object performs an operation. (20)
Activity diagram: Shows the conditional logic for the sequence of system activities needed to accomplish a business process. (20)
Actor: An external entity that interacts with the system (similar to an external entity in data flow diagramming). (20) See also Use case.
Adaptive maintenance: Changes made to a system to evolve its functionality to changing business needs or technologies. (18) See also Corrective maintenance, Perfective maintenance, Preventive maintenance.
Affinity clustering: The process of arranging planning matrix information so the clusters of information with some predetermined level or type of affinity are placed next to each other on a matrix report. (5)
Aggregation: A part-of relationship between a component object and an aggregate object. (20) See also Composition.
Alpha testing: User testing of a completed information system using simulated data. (17) See also Beta testing, System testing.
Analysis: The third phase of the SDLC in which the current system is studied and alternative replacement systems are proposed. (1)
Analysis tools: CASE tools that enable automatic checking for incomplete, inconsistent, or incorrect specifications in diagrams, forms, and reports. (4)
Application independence: The separation of data and the definition of data from the applications that use these data. (1)
Application program interface (API): Software building blocks that are used to assure that common system capabilities like user interfaces and printing are standardized as well as modules for facilitate the data exchange between clients and servers. (16)
Application server: A "middle-tier" software and hardware combination that lies between the Web server and the corporate network and systems. (11) A computing server where data analysis functions primarily reside. (16)
Application service provider: Organizations that host and run computer applications for other companies, typically on a per use or license basis. (11)
Application software: Computer software designed to support organizational functions or processes. (1)
Association: A relationship between object classes. (20) See also Association role.
Association class: An association that has attributes or operations of its own, or that participates in relationships with other classes. (20)
Association role: The end of an association where it connects to a class. (20) See also Multiplicity.
Associative entity: An entity type that associates the instances of one or more entity types and contains attributes that are peculiar to the relationship between those entity instances; also called a gerund. (10)
Asynchronous message: A message in which the sender does not have to wait for the recipient to handle the message. (20) See also Sequence Diagram, Simple message, Synchronous message.
Attribute: A named property or characteristic of an entity that is of interest to the organization. (10) See also Multivalued attribute.
Balancing: The conservation of inputs and outputs to a data flow diagram process when that process is decomposed to a lower level. (8)
Baseline modules: Software modules that have been tested, documented, and approved to be included in the most recently created version of a system. (18)
Baseline Project Plan (BPP): A major outcome and deliverable from the project initiation and planning phase, which contains the best estimate of a project's scope, benefits, costs, risks, and resource requirements. (6)
Behavior: Represents how an object acts and reacts. (20)
Beta testing: User testing of a completed information system using real data in the real user environment. (17) See also Alpha testing.
Binary relationship: A relationship between instances of two entity types. This is the most common type of relationship encountered in data modeling. (10)
Bottom-up planning: A generic information systems planning methodology that identifies and defines IS development projects based upon solving operational business problems or taking advantage of some business opportunities. (5) See also Corporate strategic planning, Top-down planning.
Boundary: The line that marks the inside and outside of a system and that sets off the system from its environment. (2)
Build routines: Guidelines that list the instructions to construct an executable system from the baseline source code. (18)
Business case: The justification for an information system, presented in terms of the tangible and intangible economic benefits and costs, and the technical and organizational feasibility of the proposed system. (6)
Business process reengineering (BPR): The search for, and implementation of, radical change in business processes to achieve breakthrough improvements in products and services. (7) See also Disruptive technologies, Key business processes.
Business rules: Specifications that preserve the integrity of a conceptual or logical data model. (10)
Candidate key: An attribute (or combination of attributes) that uniquely identifies each instance of an entity type. (10) See also Identifier, Primary key.
Cardinality: The number of instances of entity B that can (or must) be associated with each instance of entity A. (10)
Cascading style sheets (CSS): A set of style rules that tells a Web browser how to present a document. (16)
Class diagram: Shows the static structure of an object-oriented model: the object classes, their internal structure, and the relationships in which they participate.
Class-scope attribute: An attribute of a class which specifies a value common to an entire class, rather than a specific value for an instance. (20)
Client: The (front-end) portion of the client/server database system that provides the user interface and data manipulation functions. (16)
Client/server architecture: A LAN-based computing environment in which a central database server or engine performs all database commands sent to it from client workstations, and application programs on each client concentrate on user interface functions. (16) See also File server.
Closed system: A system that is cut off from its environment and does not interact with it. (2) See also Open system.
Closed-ended questions: Questions in interviews and on questionnaires that ask those responding to choose from among a set of specified responses. (7) See also Open-ended questions.
Code generators: CASE tools that enable the automatic generation of program and database definition code directly from the design documents, diagrams, forms, and reports stored in the repository. (4)
Cohesion: The extent to which a system or subsystem performs a single function. (2)
Command language interaction: A human-computer interaction method where users enter explicit statements into a system to invoke operations. (14)
Competitive strategy: The method by which an organization attempts to achieve its mission and objectives. (5)
Component: An irreducible part of aggregation of parts that make up a system; also called a subsystem. (2) See also Interrelated components.
Component diagram: Shows the software components or modules and their dependencies. (20) See also Package.
Composition: A part object that belongs to only one whole object, and that lives and dies with the whole. (20) See also Aggregation.
Computer-aided software engineering (CASE): Software tools that provide automated support for some portion of the systems development process. (3) See also Cross life-cycle CASE, I-CASE, Lower CASE, Upper CASE.
Computing infrastructure: All the resources and practices required to help people adequately use computer systems to do their primary work. (17) See also Support.
Conceptual data model: A detailed model that captures the overall structure of organizational data while being independent of any database management system or other implementation consideration. (10) See also Entity-relationship data model, Logical data model.
Concrete class: A class that can have direct instances. (20) See also Abstract class.
Condition stubs: That part of a decision table that lists the conditions relevant to the decision. (9)
Configuration management: The process of assuring that only authorized changes are made to a system. (18)
Constraint: A limit to what a system can accomplish. (2)
Constructor operation: An operation that creates a new instance of a class. (20)
Context development: A method that helps you to better understand how a system fits within existing business activities and data. (16)
Context diagram: An overview of an organizational system that shows the system boundaries, external entities that interact with the system, and the major information flows between the entities and the system. (8) See also Data flow diagram.
Cookie crumbs: A technique for showing a user where they are in a Website by placing a series of "tabs" on a Web page that shows a user where they are and where they have been. (14)
Corporate strategic planning: An ongoing process that defines the mission, objectives, and strategies of an organization. (5)
Corrective maintenance: Changes made to a system to repair flaws in its design, coding, or implementation. (18) See also Adaptive maintenance, Corrective maintenance, Perfective maintenance, Preventive maintenance.
Coupling: The extent to which subsystems depend on each other. (2)
Critical path: The shortest time in which a project can be completed. (3)
Critical path scheduling: A scheduling technique whose order and duration of a sequence of task activities directly affect the completion date of a project. (3)
Cross life cycle CASE: CASE tools designed to support activities that occur across multiple phases of the systems development life cycle. (4) See also Lower CASE, Upper CASE.
Cross referencing: A feature performed by a data dictionary that enables one description of a data item to be stored and accessed by all individuals so that a single definition for a data item is established and used. (4)
Customization: Internet sites that allow a user to customize information to their personal preferences. (16) See also Personalization.
Data: Raw facts about people, objects, and events in an organization. (1)
Data couple: A diagrammatic representation of the data exchanged between two modules in a structure chart. (15) See also Flag.
Data dictionary: The repository of all data definitions for all organizational applications. (4)
Data flow: Data in motion, moving from one place in a system to another. (1)
Data flow diagram (DFD): A picture of the movement of data between external entities and the processes and data stores within a system. (8)
Data mart: A data warehouse that is limited in scope; whose data are obtained by selecting and (where appropriate) summarized data from the enterprise data warehouse. (16)
Data store: Data at rest, which may take the form of many different physical representations. (8)
Data type: A coding scheme recognized by system software for representing organizational data. (12)
Data warehouse: A subject-oriented, integrated, time-variant, nonvolatile collection of data used in support of management decision making. (16) See also Data mart, Enterprise data warehouse (EDW).
Database: A shared collection of logically related data designed to meet the information needs of multiple users in an organization. (1)
Database engine: The (back-end) portion of the client/server database system running on the server and providing database processing and shared access function. (16)
Data-oriented approach: An overall strategy of information systems development that focuses on the ideal organization of data rather than where and how data are used. (1) See also Process-oriented approach.
Decision table: A matrix representation of the logic of a decision, which specifies the possible conditions for the decision and the resulting actions. (9) See also Action stubs, Condition stubs, Rules.
Decision tree: A graphical representation of a decision situation in which decision situation points (nodes) are connected together by arcs (one for each alternative on a decision) and terminate in ovals (the action that is the result of all of the decisions made on the path leading to that oval). (9)
Default value: A value a field will assume unless an explicit value is entered for that field. (12)
Degree: The number of entity types that participate in a relationship. (10)
Deliverable: An end product in a phase of the SDLC. (3)
Denormalization: The process of splitting or combining normalized relations into physical tables based on affinity of use of rows and fields. (12)
Design: The fourth phase of the SDLC in which the description of the recommended solution is converted into logical and then physical system specifications. (1)
Design strategy: A high-level statement about the approach to developing an information system. It includes statements on the system's functionality, hardware and system software platform, and method for acquisition. (11)
Desk checking: A testing technique in which the program code is sequentially executed manually by the reviewer. (17)
DFD completeness: The extent to which all necessary components of a data flow diagram have been included and fully described. (8)
DFD consistency: The extent to which information contained on one level of a set of nested data flow diagrams is also included on other levels. (8)
Diagramming tools: CASE tools that support the creation of graphical representations of various system elements such as process flow, data relationships, and program structures. (4)
Dialogue: The sequence of interaction between a user and a system. (14)
Dialogue diagramming: A formal method for designing and representing human—computer dialogues using box and line diagrams. (14)
Direct installation: Changing over from the old information system to a new one by turning off the old system when the new one is turned on. (17)
Discount rate: The interest rate used to compute the present value of future cash flows. (6)
Disjoint rule: Specifies that if an entity instance of the supertype is a member of one subtype, it cannot simultaneously be a member of any other subtype. (10) See also Overlap rule.
Disruptive technologies: Technologies that enable the breaking of long-held business rules that inhibit organizations from making radical business changes. (7) See also Business Process Reengineering (BPR).
Documentation generators: CASE tools that enable the easy production of both technical and user documentation in standard formats. (4)
Domain: The set of all data types and values that an attribute can assume. (10)
Domain naming system (BIND): A method for translating Internet domain names into Internet Protocol (IP) addresses. (16)
Drop-down menu: A menu positioning method that places the access point of the menu near the top line of the display; when accessed, menus open by dropping down onto the display. (14) See also Pop-up menu.
Economic feasibility: A process of identifying the financial benefits and costs associated with a development project. (6)
Electronic commerce: Internet-based communication to support day-to-day business activities. (5)
Electronic data interchange (EDI): The use of telecommunications technologies to transfer business documents between organizations. (5)
Electronic performance support system (EPSS): Component of a software package or application in which training and educational information is embedded. An EPSS can take several forms, including a tutorial, and expert system shell, and hypertext jumps to reference material. (17)
Encapsulation: The technique of hiding the internal implementation details of an object from its external view. (20) See also Abstract operation, Constructor operation, Method, Polymorphism, Query operation, Scope operation, Update operation.
Enterprise data warehouse (EDW): A centralized, integrated data warehouse that is the control point and single source of all data made available to end users for decision-support applications throughout the entire organization. (16) See also Data mart, Data warehouse.
Enterprise resource planning (ERP): systems A system that integrates individual traditional business functions into a series of modules so that a single transaction occurs seamlessly within a single information system rather than several separate systems. (11)
Entity instance (instance): A single occurrence of an entity type. (10)
Entity type: A collection of entities that share common properties or characteristics. (10)
Entity-relationship data model (E-R model): A detailed, logical representation of the entities, associations, and data elements for an organization or business area. (10) See also Conceptual data model.
Entity-relationship diagram (E-R diagram): A graphical representation of an E-R model. (10)
Environment: Everything external to a system that interacts with the system. (2)
Event: Something that takes place at a certain point in time; it is a noteworthy occurrence that triggers a state transition.(20)
Extensible style language (XSL): A specification for separating style from content when generating HTML documents. (16)
External documentation: System documentation that includes the outcome of structured diagramming techniques such as data flow and entity-relationship diagrams. (17) See also Internal documentation.
Extranet: Internet-based communication to support business-to-business activities. (5) See also Internet, Intranet.
Feasibility study: Determines if the information system makes sense for the organization from an economic and operational standpoint. (3)
Field: The smallest unit of named application data recognized by system software. (12)
File organization: A technique for physically arranging the records of a file. (12) See also Hashed file organization, Indexed file organization, Sequential file organization.
File server: A device that manages file operations and is shared by each client PC attached to a LAN. (16) See also Client/server architecture.
Flag: A diagrammatic representation of a message passed between two modules. (15) See also Data couple.
Foreign key: An attribute that appears as a nonprimary key attribute in one relation and as a primary key attribute (or part of a primary key) in another relation. (12) See also Referential integrity.
Form: A business document that contains some predefined data and may include some areas where additional data are to be filled in. An instance of a form is typically based on one database record. (13)
Form and report generators: CASE tools that support the creation of system forms and reports in order to prototype how systems will "look and feel" to users. (4)
Form interaction: A highly intuitive human-computer interaction method whereby data fields are formatted in a manner similar to paper-based forms. (14)
Formal system: The official way a system works as described in organizational documentation. (7) See also Informal system.
Functional decomposition: An iterative process of breaking the description of a system down into finer and finer detail, which creates a set of charts in which one process on a given chart is explained in greater detail on another chart. (8)
Functional dependency: A particular relationship between two attributes. For a given relation, attribute B is functionally dependent on attribute A if, for every valid value of A, that value of A uniquely determines the value of B. The functional dependence of B on A is represented by AlB. (12) See also Partial dependency, Transitive dependency.
Functional hierarchy diagram: A picture of the various tasks performed in a business and how they are related to each other. The tasks are broken down into their various parts, and all the parts are shown in the same representation. (8)
Gantt chart: A graphical representation of a project that shows each task as a horizontal bar whose length is proportional to its time for completion. (3)
Gap analysis: The process of discovering discrepancies between two or more sets of DFDs or discrepancies within a single DFD. (3)
Hashed file organization: The address for each row is determined using an algorithm. (12)
Help desk: A single point of contact for all user inquiries and problems about a particular information system or for all users in a particular department. (17) See also Computing infrastructure, Information center, Support.
Homonyms: A single attribute name that is used for two or more different attributes. (12)
HTTP (hypertext transfer protocol): A communications protocol for exchanging information on the Internet. (16)
I-CASE: An automated systems development environment that provides numerous tools to create diagrams, forms, and reports; provides analysis, reporting, and code generation facilities; and seamlessly shares and integrates data across and between tools. (4)
Icon: Graphical pictures that represent specific functions within a system. (14) See also Object-based interaction.
Identifier: A candidate key that has been selected as the unique, identifying characteristic for an entity type. (10) See also Candidate key, Primary key.
Implementation: The fifth phase of the SDLC in which the information system is coded, tested, installed, and supported in an organization. (1)
Incremental Commitment: A strategy in systems analysis and design in which the project is reviewed after each phase and continuation of the project is rejustified in each of these reviews. (5)
Index: A table used to determine the location of rows in a file that satisfy some condition. (12)
Indexed file organization: The rows are stored either sequentially or nonsequentially, and an index is created that allows software to locate individual rows. (12)
Indifferent condition: In a decision table, a condition whose value does not affect which actions are taken for two or more rules.(9)
Informal system: The way a system actually works. (7) See also Formal system.
Information center: An organizational unit whose mission is to support users in exploiting information technology. (17) See also Computing infrastructure, Help desk, Support.
Information: Data that have been processed and presented in a form suitable for human interpretation, often with the purpose of revealing trends or patterns. (1)
Information repository: Automated tools used to manage and control access to organizational business information and application portfolio as components within a comprehensive repository. (4)
Information systems analysis and design: The complex organizational process whereby computer-based information systems are developed and maintained. (1)
Information systems planning (ISP): An orderly means of accessing the information needs of an organization and defining the systems, databases, and technologies that will best satisfy those needs. (5) See also Corporate strategic planning, Top-down planning.
Informational systems: Systems designed to support decision making based on stable point-in-time or historical data. (16)
Inheritance: The property that occurs when entity types or object classes are arranged in a hierarchy and each entity type or object class assumes the attributes and methods of its ancestors; that is, those higher up in the hierarchy. Inheritance allows new but related classes to be derived from existing classes. (1)
Input: Whatever a system takes from its environment in order to fulfill its purpose. (2)
Inspections: A testing technique in which participants examine program code for predictable language-specific errors. (17)
Installation: The organizational process of changing over from the current information system to a new one. (17) See also Direct installation, Parallel installation, Phased installation, Single location installation.
Intangible benefit: A benefit derived from the creation of an information system that cannot be easily measured in dollars or with certainty. (6) See also Tangible benefit.
Intangible cost: A cost associated with an information system that cannot be easily measured in terms of dollars or with certainty. (6) See also Tangible cost.
Integrated CASE. See I-CASE.
Integration depth: A measurement of how far into the existing technology infrastructure a system penetrates. (16)
Integration testing: The process of bringing together all of the modules that a program comprises for testing purposes. Modules are typically integrated in a top-down, incremental fashion. (17)
Interface: In systems theory, point of contact where a system meets its environment or where subsystems meet each other. (2) In human-computer interaction, a method by which users interact with information systems. (14)
Internal documentation: System documentation that is part of the program source code or is generated at compile time. (17)
Internet: A large worldwide network of networks that use a common protocol to communicate with each other; a global computing network to support business-to-consumer electronic commerce. (5) See also Extranet, Intranet.
Interrelated components: Dependence of one subsystem on one or more subsystems. (2)
Intranet: Internet-based communication to support business activities within a single organization. (5) See also Internet, Extranet.
JAD session leader: The trained individual who plans and leads Joint Application Design sessions. (7)
Joint Application Design (JAD): A structured process in which users, managers, and analysts work together for several days in a series of intensive meetings to specify or review system requirements. (1)
Key business processes: The structured, measured set of activities designed to produce a specific output for a particular customer or market. (7) See also Business Process Reengineering (BPR).
Legal and contractual feasibility: The process of assessing potential legal and contractual ramifications due to the construction of a system. (6)
Level-0 diagram: A data flow diagram that represents a system's major processes, data flows, and data stores at a high level of detail. (8)
Level-n diagram: A DFD that is the result of n nested decomposition of a series of subprocesses from a process on a level-0 diagram. (8)
Lightweight graphics: The use of small simple images to allow a Web page to be more quickly displayed. (13)
Local area network (LAN): The cabling, hardware, and software used to connect workstations, computers, and file servers located in a confined geographical area (typically within one building or campus). (16)
Logical design: The part of the design phase of the SDLC in which all functional features of the system chosen for development in analysis are described independently of any computer platform. (1) See also Physical design.
Logical system description: Description of a system that focuses on the system's function and purpose without regard to how the system will be physically implemented. (2)
Lower CASE: CASE tools designed to support the implementation and maintenance phases of the systems development life cycle. (4) See also Upper CASE.
Maintainability: The ease with which software can be understood, corrected, adapted, and enhanced. (18)
Maintenance: The final phase of the SDLC in which an information system is systematically repaired and improved. (1) Changes made to a system to fix or enhance its functionality. (18) See also Adaptive maintenance, Corrective maintenance, Perfective maintenance, Preventive maintenance.
Mean time between failures (MTBF): A measurement of error occurrences that can be tracked over time to indicate the quality of a system. (18)
Menu interaction: A human-computer interaction method where a list of system options is provided and a specific command is invoked by user selection of a menu option. (14) See also Drop-down menu, Pop-up menu.
Method: The implementation of an operation. (20)
Middleware: A combination of hardware, software, and communication technologies that bring together data management, presentation, and analysis into a three-tiered client/server environment. (16)
Mission statement: A statement that makes it clear what business a company is in. (5)
Modularity: Dividing a system up into chunks or modules of a relatively uniform size. (2) See also Cohesion, Coupling.
Multiplicity: Indicates how many objects participate in a given relationship. (20)
Multivalued attribute: An attribute that may take on more than one value for each entity instance. (10)
Natural language interaction: A human-computer interaction method whereby inputs to and outputs from a computer-based application are in a conventional speaking language such as English. (14)
Nominal Group Technique: A facilitated process that supports idea generation by groups. At the beginning of the process, group members work alone to generate ideas, which are then pooled under the guidance of a trained facilitator. (7)
Normalization: The process of converting complex data structures into simple, stable data structures. (12)
Null value: A special field value, distinct from 0, blank, or any other value, that indicates that the value for the field is missing or otherwise unknown. (12)
Object: A structure that encapsulates (or packages) attributes and methods that operate on those attributes. An object is an abstraction of a real-world thing in which data and processes are placed together to model the structure and behavior of the real-world object. (1) An entity that has a well-defined role in the application domain, and has state, behavior, and identity. (20) See also Object class, Object diagram.
Object class: A logical grouping of objects that have the same (or similar) attributes and behaviors (methods). (1, 20) See also Abstract class, Concrete class.
Object diagram: A graph of instances that are compatible with a given class diagram. (20)
Object-based interaction: A human-computer interaction method where symbols are used to represent commands or functions. (14) See also Icon.
Objective statements: A series of statements that express an organization's qualitative and quantitative goals for reaching a desired future position. (5)
Object-oriented analysis and design (OOAD): Systems development methodologies and techniques based on objects rather than data or processes. (1)
One-time cost: A cost associated with project start-up and development, or system start-up. (6)
On-line analytical processing (OLAP): The use of graphical software tools that provide complex analysis of data stored in a database. (16) See also Data mart, Enterprise data warehouse.
On-line transaction processing (OLTP): The immediate automated responses to the requests of users. (16)
Open system: A system that interacts freely with its environment, taking input and returning output. (2)
Open-ended questions: Questions in interviews and on questionnaires that have no prespecified answers. (7) See also Closed-ended questions.
Operation: A function or a service that is provided by all the instances of a class.(20)
Operational feasibility: The process of assessing the degree to which a proposed system solves business problems or takes advantage of business opportunities. (6)
Operational systems: Systems that are used to interact with customers and run a business in real time. (16)
Organizational breadth: A measurement that tracks the core business functions affected by a system. (16)
Output: Whatever a system returns to its environment in order to fulfill it purpose. (2)
Outsourcing: The practice of turning-over responsibility of some to all of an organization's information systems applications and operations to an outside firm. (11)
Overlap rule: Specifies that an entity instance can simultaneously be a member of two (or more) subtypes. (10) See also Disjoint rule.
Overriding: The process of replacing a method inherited from a superclass by a more specific implementation of that method in a subclass. (20)
Package: A set of cohesive, tightly coupled classes representing a subsystem. (20) See also Component diagram.
Parallel installation: Running the old information system and the new one at the same time until management decides the old system can be turned off. (17)
Partial specialization rule: Specifies that an entity instance of the supertype is allowed not to belong to any subtype. (10) See also Total specialization rule.
Perfective maintenance: Changes made to a system to add new features or to improve performance. (18) See also Adaptive maintenance, Corrective maintenance, Preventive maintenance.
Personalization: Providing Internet content to users based upon knowledge of that customer. (16) See also Customization.
PERT chart: A diagram that depicts project tasks and their interrelationships. PERT stands for Program Evaluation Review Technique. (3)
Phased installation: Changing from the old information system to the new one incrementally, starting with one or a few functional components and then gradually extending the installation to cover the whole new system. (17)
Physical design: The part of the design phase of the SDLC in which the logical specifications of the system from logical design are transformed into technology- specific details from which all programming and system construction can be accomplished. (1) See also Logical design.
Physical file: A named set of table rows stored in a contiguous section of secondary memory. (12)
Physical system description: Description of a system that focuses on how the system will be materially constructed. (2)
Physical table: A named set of rows and columns that specifies the fields in each row of the table. (12)
Pointer: A field of data that can be used to locate a related field or row of data. (12)
Political feasibility: The process of evaluating how key stakeholders within the organization view the proposed system. (6)
Polymorphism: The same operation may apply to two or more classes in different ways. (20)
Pop-up menu: A menu positioning method that places a menu near the current cursor position. (14) See also Drop-down menu.
Present value: The current value of a future cash flow. (6)
Preventive maintenance: Changes made to a system to avoid possible future problems. (18) See also Adaptive maintenance, Corrective maintenance, Perfective maintenance.
Primary key: An attribute whose value is unique across all occurrences of a relation. (12) See also Candidate key, Identifier, Secondary key.
Primitive DFD: The lowest level of decomposition for a data flow diagram. (8)
Process: The work or actions performed on data so that they are transformed, stored, or distributed. (8)
Processing logic: The steps by which data are transformed or moved and a description of the events that trigger these steps. (1)
Process-oriented approach: An overall strategy to information systems development that focuses on how and when data are moved through and changed by an information system. (1) See also Data-oriented approach.
Project: A planned undertaking of related activities to reach an objective that has a beginning and an end. (3)
Project closedown: The final phase of the project management process, which focuses on bringing a project to an end. (3)
Project execution: The third phase of the project management process, in which the plans created in the prior phases (project initiation and planning) are put into action. (3)
Project identification and selection: The first place of the SDLC in which an organization's total information system needs are identified, analyzed, prioritized, and arranged. (1)
Project initiation: The first phase of the project management process, in which activities are performed to assess the size, scope, and complexity of the project and to establish procedures to support later project activities. (3)
Project initiation and planning: The second phase of the SDLC in which a potential information systems project is explained and an argument for continuing or not continuing with the project is presented; a detailed plan is also developed for conducting the remaining phases of the SDLC for the proposed system. (1)
Project management: A controlled process of initiating, planning, executing, and closing down a project. (3)
Project manager: A systems analyst with a diverse set of skills--management, leadership, technical, conflict management, and customer relationship--who is responsible for initiating, planning, executing, and closing down a project. (62)
Project planning: The second phase of the project management process, which focuses on defining clear, discrete activities and the work needed to complete each activity within a single project. (3)
Project workbook: An on-line or hard-copy repository for all project correspondence, inputs, outputs, deliverables, procedures, and standards that is used for performing project audits, orientation of new team members, communication with management and customers, identifying future projects, and performing post-project reviews. (3) See also Repository.
Prototyping: An iterative process of systems development in which requirements are converted to a working system that is continually revised through close work between an analyst and users. (1) See also Rapid Application Development (RAD).
Pseudocode: A method for representing the instructions in a module with language very similar to computer programming code. (15)
Purpose: The overall goal or function of a system. (2)
Query operation: An operation that accesses the state of an object but does not alter the state. (20) See also Abstract operation, Query operation, Update operation.
Rapid Application Development (RAD): Systems development methodology created to radically decrease the time needed to design and implement information systems. RAD relies on extensive user involvement, Joint Application Design sessions, prototyping, integrated CASE tools, and code generators. (19) See also Prototyping.
Recurring costs: A cost resulting from the ongoing evolution and use of a system. (6)
Recursive foreign key: A foreign key in a relation that references the primary key values of that same relation. (12)
Reengineering: Automated tools that read program source code as input, perform an analysis of the program's data and logic, and then automatically, or interactively with a systems analyst, alter an existing system in an effort to improve its quality or performance. (4) See also CASE.
Referential integrity: An integrity constraint specifying that the value (or existence) of an attribute in one relation depends on the value (or existence) of the same attribute in another relation. (12) See also Foreign key.
Relational database model: Data represented as a set of related tables or relations. (12)
Relations: A named, two-dimensional table of data. Each relation consists of a set of named columns and an arbitrary number of unnamed rows. (12)
Relationship: An association between the instances of one or more entity types that is of interest to the organization. (10)
Repeating group: A set of two or more multivalued attributes that are logically related. (10)
Report: A business document that contains only predefined data; it is a passive document used solely for reading or viewing. A report typically contains data from many unrelated records or transactions. (13)
Repository: A centralized database that contains all diagrams, forms and report definitions, data structure, data definitions, process flows and logic, and definitions of other organizational and system components; it provides a set of mechanisms and structures to achieve seamless data-to-tool and data-to-data integration. (4) See also Data dictionary, I-CASE, Information repository, Project workbook.
Request for proposal (RFP): An RFP is a document provided to vendors to ask them to propose hardware and system software that will meet the requirements of your new system. (11)
Resources: Any person, group of people, piece of equipment, or material used in accomplishing an activity. (3)
Reusability: The ability to design software modules in a manner so that they can be used again and again in different systems without significant modification. (4)
Reverse engineering: Automated tools that read program source code as input and create graphical and textual representations of program design-level information such as program control structures, data structures, logical flows, and data flow. (4) See also CASE.
Rules: That part of a decision table that specifies which actions are to be followed for a given set of conditions. (9)
Scalable: The ability to seamlessly upgrade the capabilities of the system through either hardware upgrades, software upgrades, or both. (11)
Schedule feasibility: The process of assessing the degree to which the potential time frame and completion dates for all major activities within a project meet organizational deadlines and constraints for affecting change. (6)
Scope operation: An operation that applies to a class rather than an object instance. (20)
Scribe: The person who makes detailed notes of the happenings at a Joint Application Design session. (7)
Second normal form (2NF): A relation is in second normal form if every nonprimary key attribute is functionally dependent on the whole primary key. (12) See also Functional dependency, Partial dependency.
Secondary key: One or a combination of fields for which more than one row may have the same combination of values. (12) See also Primary key.
Sequence diagram: Depicts the interactions among objects during a certain period of time. (20)
Sequential file organization: The rows in the file are stored in sequence according to a primary key value. (12)
Simple message: A message that transfers control from the sender to the recipient without describing the details of the communication. (20) See also Asynchronous message, Sequence diagram, Synchronous message.
Single location installation: Trying out a new information system at one site and using the experience to decide if and how the new system should be deployed throughout the organization. (17)
Slack time: The amount of time that an activity can be delayed without delaying the project. (3)
Source/Sink: The origin and/or destination of data, sometimes referred to as external entities. (8)
Stakeholder: A person who has an interest in an existing or new information system. (1)
State: Encompasses an object's properties (attributes and relationships) and the values those properties have. (20) See also Behavior.
State diagram A model of the states of an object and the events that cause the object to change from one state to another. (20)
State transition: Changes in the attributes of an object or in the links an object has with other objects. (20)
Statement of Work (SOW): Document prepared for the customer during project initiation and planning that describes what the project will deliver and outlines generally at a high level all work required to complete the project. (6)
Structure chart: Hierarchical diagram that shows how an information system is organized. (15)
Structured English: Modified form of the English language used to specify the logic of information system processes. Although there is no single standard, Structured English typically relies on action verbs and noun phrases and contains no adjectives or adverbs. (9)
Stub testing: A technique used in testing modules, especially where modules are written and tested in a top-down fashion, where a few lines of code are used to substitute for subordinate modules. (17)
Subtype: A subgrouping of the entities in an entity type that is meaningful to the organization and that shares common attributes or relationships distinct from other subgroupings. (10) See also Supertype.
Supertype: A generic entity type that has a relationship with one or more subtypes. (10) See also Subtype.
Support: Providing ongoing educational and problem-solving assistance to information system users. For in-house developed systems, support materials and jobs will have to be prepared or designed as part of the implementation process. (17) See also Computing infrastructure, Help desk, Information center.
Synchronous message: A type of message in which the caller has to wait for the receiving object to finish executing the called operation before it can resume execution itself. (20) See also Asynchronous message, Sequence diagram, Simple message.
Synonyms: Two different names that are used for the same attribute. (12)
System: An interrelated set of components, with an identifiable boundary, working together for some purpose. (2) See also Closed system, Open system.
System documentation: Detailed information about a system's design specifications, its internal workings, and its functionality. (17)
System librarian: A person responsible for controlling the checking out and checking in of baseline modules for a system when a system is being developed or maintained. (18)
System testing: The bringing together of all the programs that a system comprises for testing purposes. Programs are typically integrated in a top-down, incremental fashion. (17) See also Acceptance testing, Alpha testing, Beta testing, Integration testing, Stub testing.
Systems analysis: The organizational role most responsible for the analysis and design of information systems. (1)
Systems development life cycle (SDLC): The traditional methodology used to develop, maintain, and replace information systems. (1)
Systems development methodology: A standard process followed in an organization to conduct all the steps necessary to analyze, design, implement, and maintain information systems. (1)
Tangible benefit: A benefit derived from the creation of an information system that can be measured in dollars and with certainty. (6) See also Intangible benefit.
Tangible cost: A cost associated with an information system that can be measured in dollars and with certainty. (6) See also Intangible cost.
Technical feasibility: The process of assessing the development organization's ability to construct a proposed system. (6)
Template-based HTML: Templates to display and process common attributes of higher-level, more abstract items. (13)
Ternary relationship: A simultaneous relationship among instances of three entity types. (10)
Thin client: A client device designed so that most processing and data storage occurs on the server. (16)
Third normal form (3NF): A relation is in third normal form if it is in second normal form and there are no functional (transitive) dependencies between two (or more) nonprimary key attributes. (12)
Three-tiered client/server: Advanced client/server architecture in which there are three logical and distinct applications-data management, presentation, and analysis-which are combined to create a single information system. (16)
Top-down planning: A generic information systems planning methodology that attempts to gain a broad understanding of the information system needs of the entire organization. (5) See also Bottom-up planning.
Total specialization rule: Specifies that each entity instance of the supertype must be a member of some subtype in the relationship. (10) See also Partial specialization rule.
Triggering operation (trigger): An assertion or rule that governs the validity of data manipulation operations such as insert, update, and delete. (10)
Unary relationship (recursive relationship): A relationship between the instances of one entity type. (10)
Unit testing: Each module is tested alone in an attempt to discover any errors in its code. (17)
Update operation: An operation that alters the state of an object. (20) See also Abstract operation, Constructor operation, Query operation.
Upper CASE: CASE tools designed to support the information planning and the project identification and selection, project initiation and planning, analysis, and design phases of the systems development life cycle. (4) See also Lower CASE. Usability An overall evaluation of how a system performs in supporting a particular user for a particular task. (13)
Usability: An overall evaluation of how a system performs in supporting a particular user for a particular task. (13)
Use case: A complete sequence of related actions initiated by an actor to accomplish a specific goal; it represents a specific way of using the system. (20)
Use-case diagram: A diagram that depicts the use cases and actors for a system. (20)
User documentation: Written or other visual information about an application system, how it works, and how to use it. (17)
Value chain analysis: Analyzing an organization's activities to determine where value is added to products and/or services and the costs incurred for doing so; usually also includes a comparison with the activities, added value, and costs of other organizations for the purpose of making improvements in the organization's operations and performance. (5)
Walkthrough: A peer group review of any product created during the systems development process; also called a structured walkthrough. (6)
Web server: A computer that is connected to the Internet and stores files written in HTML (hypertext markup language) that are publicly available through an Internet connection. (11)
Well-structured relation (or table): A relation that contains a minimum amount of redundancy and allows users to insert, modify, and delete the rows without errors or inconsistencies. A relation that contains a minimum amount of redundancy and allows users to insert, modify, and delete the rows without errors or inconsistencies. (12) See also Normalization.
Work breakdown structure: The process of dividing the project into manageable tasks and logically ordering them to ensure a smooth evolution between tasks. (3)
XML (extensible markup language): An Internet authoring language that allows designers to create customized tags, enabling the definition, transmission, validation, and interpretation of data between applications. (16)