The foundation of relational database design--paradigm

Source: Internet
Author: User

First normal: There are no duplicate columns.

Second paradigm: To have a unique identity.

The third paradigm: not dependent on non-primary keys.

Implemented the third paradigm, which shows that the first and second paradigm have been realized.

does not conform to the third paradigm, the database table will have a pruning exception, and generate a large amount of redundant data.

For a better understanding of the meaning of the three paradigms, please refer to: http://baike.baidu.com/view/26218.htm

The foundation of relational database design--paradigm

Contact Us

The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion; products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the content of the page makes you feel confusing, please write us an email, we will handle the problem within 5 days after receiving your email.

If you find any instances of plagiarism from the community, please send an email to: info-contact@alibabacloud.com and provide relevant evidence. A staff member will contact you within 5 working days.

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

  • Sales Support

    1 on 1 presale consultation

  • After-Sales Support

    24/7 Technical Support 6 Free Tickets per Quarter Faster Response

  • Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.