用一个例子理解1NF,2NF,3NF,BCNF。。(此篇纯水,无价值) 设计一个论坛的数据库: (1) 用户:用户名,email,主页,电话,联系地址 (2) 帖子:发帖标题,发帖内容,回复标题,回复内容 第一次:将数据库设计为仅存在表。 create table1(用户名 email 主页 电话 联系地址 发帖标题 发帖内容 回复标题 回复内容) 很显然...
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The Mughal painting techniques were inspired by the Persian rulers in North India and this school of painting had a lot of impact on the genre of miniature paintings as well. A. 正确 B. 错误 查看完整题目与答案 ( )组件是一种列表选择控件。 A. RadioGroup B. RadioButton C. CheckBox...
It is achieved by applying a set of rules and procedures to a database, known as normalization forms. There are several normalization forms, including the First Normal Form (1NF), Second Normal Form (2NF), Third Normal Form (3NF), Boyce-Codd Normal Form (BCNF), and the Fourth Normal ...
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College costs vary quite a bit, depending upon the type of school attended. For example, at many of the more expensive private schools, annual costs (including tuition, room, board, books, travel to and from home, and other expenses) may ex..
Security Insights Additional navigation options Files master js src storage fonts Aldrich Lora Nunito Sans Raleway Roboto Times New Roman Ubuntu data.json index.json .jshintrc README.md foooont.jpg index.html File metadata and controls executable file ...
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