翻訳と辞書 Words near each other ・ data warehouse ・ data warehousing ・ data-text ・ data/basic ・ database ・ database administrator ・ database analyst ・ database machine ・ database management system ・ database manager ・ database normalisation ・ database query language ・ database server ・ databus ・ datacenter manager ・ datacode i ・ datacom ・ datagram ・ datakit ・ dataless management services 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 database normalisation ： FOLDOC database normalisation A series of steps followed to obtain a database design that allows for efficient access and storage of data in a relational database. These steps reduce data redundancy and the chances of data becoming inconsistent. A table in a relational database is said to be in normal form if it satisfies certain constraints. {Codd}'s original work defined three such forms but there are now five generally accepted steps of normalisation. The output of the first step is called First Normal Form (1NF), the output of the second step is Second Normal Form (2NF), etc. First Normal Form eliminates {repeating groups} by putting each value of a multi-valued attribute into a new row. Second Normal Form eliminates {functional dependencies} on a partial key by putting the fields in a separate table from those that are dependent on the whole key. Third Normal Form eliminates functional dependencies on non-key fields by putting them in a separate tab 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.