Term
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Definition
| Set of related components that work together to accomplish some objectives; objectives are accomplished by interacting with the environment and performing functions |
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Definition
| Manipulates data rather than a physical object; accepts data from its environment, processes data, and produces output data for decision making |
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Term
| Preliminary Investigation Phase |
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Definition
| Produces a problem statement and feasibility study; includes objectives, constraints, and scope of the system; identifies costs and benefits |
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Term
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Definition
| Produces requirements describing processes, data, and environment interactions; diagramming techniques are used to document processes, data, and environment interactions; current system is studied and users of proposed system are interviewed to produce the requirements |
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Term
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Definition
| Produces a plan to efficiently implement the requirements; design specifications are created for processes, data, and environment interaction; focuses on choices to optimize resources given constraints |
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| Systems Implementation Phase |
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Definition
| Produces executable code, databases, and user documentation; design specs are coded and tested; before making the new system operational, a transition plan from the old system to the new system is devised; to gain confidence and experience with the new system, the two systems may be run parallel to each other for awhile |
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Term
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Definition
| Produces corrections, changes, and enhancements to an operating information system; commences when an information system becomes operational; comprises activities from all the other phases; ends when a replacement system is deployed and the current system is retired; can last decades |
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Definition
| Scaled-down versions of a system; used to clarify requirements |
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Term
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Definition
| Describes the kinds of data and relationships |
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Definition
| Describes relationships among processes |
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| Environment Interaction Model |
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Definition
| Describes relationships between events and processes |
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Term
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Definition
| Database represents all important parts of the information system |
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Term
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Definition
| Each part of the database has only one meaning |
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Definition
| Database contains values perceived by the user |
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Definition
| Business changes are posted to the database without excessive delays |
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Term
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Definition
| Failures or interference do not corrupt database |
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Term
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Definition
| Different parts of the database do not conflict |
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Term
| Entity Relationship Diagram (ERD) |
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Definition
| Graphical representation that depicts things of interest (entities) and relationships among entities |
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Term
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Definition
| Transforms ERDs into table designs using conversion rules, (links to other related tables), and other constraints |
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Definition
| Removes redundancies in a table design using constraints or dependencies among columns |
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Term
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Definition
| Auxiliary file that can improve performance; can improve performance on retrievals but reduce performance on updatesData |
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Definition
| Designer decides how data should be clustered or located close together on a disk |
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Term
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Definition
| An ERD is constructed for each group of users; a view is typically small enough for a single person to design; multiple designers can work on views covering different parts of the database |
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Term
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Definition
| Process that merges views into a complete and consistent conceptual schema |
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Definition
| Qualitative, subjective, and people-oriented |
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Definition
| Quantitative, objective, and data intensive |
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Term
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Definition
| Mostly involved in the conceptual data modeling and logical database design phases |
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Term
| Database Performance Experts |
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Definition
| Mostly involved in the distribution and physical design phases |
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Term
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Definition
| Database of the CASE tool; also known as the repository or encyclopedia |
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Term
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Definition
| Group of changes and enhancements to a system that is released together |
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