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Answer 1

A:

Normalization is all about eliminating redundant data: a quick glance at the tables will tell you that a lot of fields are repeated.

Take for example the second table: by mixing staff and branch details, we end up repeating a lot of stuff. Obviously a person always has a fixed name, and a branch has a fixed address, so put this information into a separate staff table and a separate branch table. Then the original table will have only pairs of staff no. and branch no., and any information unique to each pair, such as hours per week.

I hope you get the idea, and that you can answer the rest of the problem by yourself.

casablanca 2010-10-25 01:01:35

Answer 2

A:

Here's what's i've got for Question 1 there. Don't know if this is right or not. Please do correct me. alt text

James1 2010-10-25 01:03:14

That's right. . .

Larry Lustig 2010-10-25 01:23:08

@Larry: can i do it this way though? is this alright? http://i396.photobucket.com/albums/pp44/yoyoyaya_2008/Capture1-3.jpg

James1 2010-10-25 01:27:25

Definitely not! What happens if a branch changes its name? Three updates! Your first attempt, above, is correct.

Larry Lustig 2010-10-25 01:30:35

Answer 3

A:

Marcelo Cantos 2010-10-25 01:03:38

@Marcelo: thanks a lot for your explanations, but it's still kinda a puzzle to me though. Would you mind covert those tables into 1NF, 2NF and 3NF, maybe its easier for me to understand? Although, i think i've got question 1 answered there. the answer at the bottom there.

James1 2010-10-25 01:19:33

I've read some websites about this and it says there are 3 golden rules to do this thing: 1NF: No repeating elements or groups of elements, 2NF: No partial dependencies on a concatenated key and 3NF: No dependencies on non-key attributes but i'm still not sure how to convert those tables.

James1 2010-10-25 01:20:35

Yes I would mind showing you the answer. You need to do your own homework. I have, however, appended some further advice to my answer. It may be quite different to what you've read in your text books, but if you get your head around the concepts as I describe them, you'll come away with a much better understanding of what normalization theory is all about.

Marcelo Cantos 2010-10-25 01:33:47

Answer 4

A:

Here is the answer the my question 2 above. Please guys, help me to correct this. This is what i've come up so far. alt text

James1 2010-10-26 04:51:10

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Normalization - 1NF, 2NF and 3NF

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