翻訳と辞書 Words near each other ・ First Citizen (novel) ・ First Citizens BancShares ・ First Citizens Bank (Trinidad and Tobago) ・ First Citizens Bank of South Carolina ・ First Citizens Plaza ・ First Citizens' Federal Credit Union ・ First City Building ・ First City Hall (Ottawa) ・ First City Monument Bank ・ First City Regiment ・ First City Tower ・ First Civil Service Commissioner ・ First Civil War ・ First class ・ First class (aviation) ・ First class (computing) ・ First Class (game show) ・ First Class (TV series) ・ First Class 8 ・ First Class All the Way ・ First Class Chefs ・ First class constraint ・ First Class CW Operators' Club ・ First class facilities of the RMS Titanic ・ First Class Kloss! ・ First Class Scout (Boy Scouts of America) ・ First Class Thieves ・ First class travel ・ First Coast ・ First Coast Commuter Rail Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク First class (computing) ： ウィキペディア英語版 First class (computing) In database modeling, a first class item is one that has an identity independent of any other item. The identity allows the item to persist when its attributes change, and allows other items to claim relationships with the item. As a general rule, first class items represent things rather than relationships. For example, the database representations of a human and of a company are each first class items. However, the fact that the person is an employee of that company is not a first class item. Likewise, data ''about'' that relationship, e.g. information about the salary the company pays to its employee, is not a first class item. Typically, a relational database will include several tables, each of which contains rows representing first class items of a given type (e.g. a table of people, a table of companies). It will also contain other tables representing relationships between these first class items. In a table representing first class items, one column of the table will typically contain a different integer assigned to each row (effectively, to each item) as a unique identifier: that is to say, unique for objects of this type; objects of different types, represented in different tables, can coincidentally have the same identifier, but the coincidence is meaningless. In a relational database, a table representing a ''relationship'' between two or more first class items (or data about that relationship) will usually ''not'' have special identifiers for its rows. Instead these rows will be identified by an ordered tuple consisting of unique identifiers of the first class items involved in the relationship. 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「First class (computing)」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.