ISOM pwpt ch 7 continued

ISOM pwpt ch 7 continued - Relational Definitions Relation...

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2/17/11 17-1 Relational Definitions Relation a two dimensional table Relational Database a collection of related relations within one database every relation has a unique name.
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2/17/11 27-2 Relational Definitions Synonyms: Table = Relation = Relational Table Column = Attribute = Field Row = Tuple = Record
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2/17/11 37-3 Relational Definitions Not every table is a relation Within a Relation: Columns have unique names. Every row is unique. Every column value for every row is single-valued All values in a column are values from the same domain.
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2/17/11 47-4 Relational Definitions Relational Table Not a Relational Table
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2/17/11 57-5 Relational Definitions Relational Table Exact Same Relational Table (order of rows and columns is irrelevant)
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2/17/11 67-6 Relational Keys and Structures Primary Key uniquely identifies a row in a relational table equivalent to the Key attribute in the ER model Foreign Key used to implement relationships (one-to- one, one-to-many, many-to-many) in relational model depicted by the Referential Integrity
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ISOM pwpt ch 7 continued - Relational Definitions Relation...

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