RissRoss: Normalization Questions asks many questions
1) It says in the coursepack and handouts that for 1NF you should remove all repeating groups and put them in another relation. However, I believe it also says that there is only one relation (or table) when the database is in the 1NF form only. Therefore, how does this work? And if this is the case, what would another table of the repeating groups come to look like, what fields should be included?
The key point is to get rid of the repeating group, things like Address1, Address2, etc. and just make a single well defined attribute (e.g., Address). Either at this point or later in the process, this attribute will go in its own table with its own primary key.
2) What does it mean when it says that X & Y of Multi-Value Dependency (MVD) can contain either single or composite attributes?
Composite attribute just means more than one attribute together.
3) What does entity refer to when talking about normalization? Does it refer to a particular field (column name) of the relation?
Is there a specific use of the word that is confusing?
4) For Handout Normalization Exercise #2, how is sell date part of the primary key? What if the customer hasn't sold the stock yet, and therefore the value is null? because a primary key can't have a null value in it, and therefore it does not make sense to me.
I addressed this question in a previous discussion with maulin that occurred one month ago today.