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Related Flashcards
Cards In This Set
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Entity
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An object in the real world we are going to model in the database-person, place, thing or event
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Attribute
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A characteristic or quality of an entity
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Character
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The most basic logical data element that can be observed-represented by one byte
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Field/column
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A grouping of related characters-represents an attribute of some entity
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Reocrd/row
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A grouping of attributes that describe an entity
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Table (or file)
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A group of related data records
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Database
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A collection of logically related data elements, usually organized in related tables
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Hierarchial Structure
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Treelike structure of one-to-many parent-child relationships (each child can have only one parent)
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Network Structure
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Similar to hierarchial but allows many-to-many relationships (a child record can have more than one parent)
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Object-Oriented Structure
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Combines the data of interest and the processes that act on that data into a structure called an object-this combination process is called encapsulation
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Inheritance
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Allows use of some/all of the characteristics of a parent object in the creation of a child object
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Select
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-create a subset of records that meets a criterion(all students in IST 301)
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Join
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-temporarily combine two or more tables for comparison(all students on summerfield 5th floor at 1pm)
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Project
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Create a subset of the columns in the temporary tables
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Primary key
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-uniquely identifies each record (like a KU Id number)
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