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In computing, the attribute domain is the set of values allowed in an attribute.〔.〕 For example: Rooms in hotel (1-300) Age (1-99) Married (yes or no) Nationality (Nepalese, Indian, American, or British) Colors (Red, Yellow, Green) For the relational model it is a requirement that each part of a tuple be atomic.〔.〕 The consequence is that each value in the tuple must be of some basic type, like a string or an integer. For the elementary type to be atomic it cannot be broken into more pieces. Alas, the domain is an elementary type, and attribute domain the domain a given attribute belongs to an abstraction belonging to or characteristic of an entity. ==References== 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「attribute domain」の詳細全文を読む スポンサード リンク
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