1 / 6

Entity Relationship Diagrams (ERDs)

Entity Relationship Diagrams (ERDs). 1. ∞. Entity Relationship Diagrams. S. C. T. Entity Relationship Diagrams. Students go on courses Tutors teach courses. S. C. T. Entity Relationship Diagrams. One student can be on one or more courses A course has one or more students

aida
Télécharger la présentation

Entity Relationship Diagrams (ERDs)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Entity Relationship Diagrams(ERDs)

  2. 1 ∞ Entity Relationship Diagrams

  3. S C T Entity Relationship Diagrams Students go on courses Tutors teach courses

  4. S C T Entity Relationship Diagrams One student can be on one or more courses A course has one or more students Tutors teach one or more courses

  5. Entity Relationship Diagrams Problem: We can’t have a many-to-many so we need to create a link entity

  6. Entity Relationship Diagrams S C One student is enrolled on one or more courses A course can have one or more students enrolled on it T E

More Related