04-19-14, 08:10 #1Registered User
- Join Date
- Apr 2014
How to convert this relation to 2NF?
In my Entity Relationship Diagram, an entity type TEACHER had a relationship of TEACH with another entity type called CLASS. CLASS was a week entity type of TEACHER,so when mapping to a Relational Data Model, I had introduced the Primary Key, named TCode, of TEACHER into CLASS as a Foreign Key.
Now, the relation named CLASS contains the following attributes: ICode (FK), CDate, CStartTime, CEndTime.
Primary Key is composite of ICode, CDate, CStartTime.
Following partial dependency exists here: CStartTime -> CEndTime
I need some help on how to convert this into 2NF. I have read up and seen examples of customers and shops etc. etc. but I could not map the understanding into my example.
I'll appreciate if somebody can tell what to do and why?
04-19-14, 19:35 #2Resident Curmudgeon
- Join Date
- Feb 2004
- In front of the computer
Start with the Marc Rettig Normalization Poster. It will help you understand the process of getting from un-normalized up to 5NF (Fifth Normal Form) if you need to go that far.
Once you have a normalized design, come back with any questions... The chances of someone at DBForums doing your homework for you are pretty slim, but we'll gladly help by answering specific questions.
-PatPIn theory, theory and practice are identical. In practice, theory and practice are unrelated.