normalization estate exercise

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normalization estate exercise

mobildiho

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Points: 101
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August 5, 2014 at 2:23 pm

#309726

got this relational database exercise and didn't move from here but I know whats on the last table.
all normal forms are shown using unf to 3nf.yet I was able to only do 3nf but did know unf,1nf,2nf
this is the problem to normalize
PropertyCode
PropertyType
Address
Asking Price
New Offer
Commission
Vendor A/C Code
Name
Address
Tel. No.
NegotiatorCode
Name
Mobile
Email
Solicitor A/C Code
Name
Address
Tel. No
Prospect Code
Name
Address
Tel. No.
.............................................................................................................................................................
using the bellow method
| UNF | 1NF | 2NF | 3NF |

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Gail Shaw SSC Guru Points: 1004504 More actions · Answer 1

Homework?

What have you got so far and where exactly are you stuck?

Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

We walk in the dark places no others will enter
We stand on the bridge and no one may pass

mobildiho SSC Enthusiast Points: 101 More actions · Answer 2

I have only done the 3nf am stuck with the beginning UNF,1NF ,2NF

if you don't mind I can mail you the sample method as I couldn't upload it

mobildiho SSC Enthusiast Points: 101 More actions · Answer 3

mobildiho

SSC Enthusiast

Points: 101

August 5, 2014 at 2:45 pm

#1735382

yes its homework

Gail Shaw SSC Guru Points: 1004504 More actions · Answer 4

You can mail it to me, I'll just delete it. I am not doing your homework for you. I don't need the practice, I don't need the qualification.

To do 3rd normal form requires that the table already be in 2nd normal form, so either you've done them all or you've done nothing.

Again, what do you have so far and where exactly are you stuck? We'll help, we're not doing it for you.

Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

We walk in the dark places no others will enter
We stand on the bridge and no one may pass

pietlinden SSC Guru Points: 63512 More actions · Answer 5

How can you get to 3NF if you don't go through 1NF and 2NF first? Interesting concept.

Here's a pretty easy primer on Normal Forms. If you apply them in sequence (and completely), you should be off and running.

mobildiho SSC Enthusiast Points: 101 More actions · Answer 6

here is my mine

3nf

Property Code PK

Property type

Vendor A/C Code FK

Negotiator Code FK

Negotiator Code PK

NAME

Code PK

Solicitor FK

SolicitorCode PK

Name

Mobile

ProspectCode PK

Date

Gail Shaw SSC Guru Points: 1004504 More actions · Answer 7

pietlinden (8/5/2014)
How can you get to 3NF if you don't go through 1NF and 2NF first?

You can't. The definition of 3rd normal form goes "To be in 3rd normal form, a table must be in 2nd normal form and ..."

mobildiho: Start from 1st normal form. You can't go straight to 3rd. Take the starting design, put it into first normal form. Make sure it's right. Take that, put it into 2nd normal form, make sure it's right. Finally, take the tables in 3nd normal form and put them into 3rd. It's a progression.

Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

We walk in the dark places no others will enter
We stand on the bridge and no one may pass

mobildiho SSC Enthusiast Points: 101 More actions · Answer 8

yes but the is composite/ compound key that will be at the 2nf..ok thanks so far

Gail Shaw SSC Guru Points: 1004504 More actions · Answer 9

No, you can't have parts of a table in one form and parts in another. Either the table is 3rd normal form or it isn't. You can't say that it's part 3rd, part 2nd, etc.

2nd normal form doesn't require composite keys.

I suspect you may want to go back to your tutor/lecturer and go over the normal forms with them again.

Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

We walk in the dark places no others will enter
We stand on the bridge and no one may pass

sqlvogel SSCrazy Eights Points: 9526 More actions · Answer 10

pietlinden (8/5/2014)
How can you get to 3NF if you don't go through 1NF and 2NF first?

Very easily, you just need to ensure that the non-trivial determinants of every non-key attribute are superkeys. Outside of an academic exercise I'm surprised if anyone would go through the trouble of creating a table design that satisifies 1NF but not 2NF and then refine it to make it satisfy 2NF and then refine it again to make it 3NF. I've certainly never bothered with such exercises outside the classroom.

2NF and 3NF are of mostly historical or academic importance anyway. Most of the time it makes sense to design to Boyce-Codd / 5th Normal Form and don't concern yourself with 3NF except in cases where you need to denormalize in order to enforce certain business rules.

Gail Shaw SSC Guru Points: 1004504 More actions · Answer 11

sqlvogel (8/6/2014)
pietlinden (8/5/2014)
How can you get to 3NF if you don't go through 1NF and 2NF first?
Very easily, you just need to ensure that the non-trivial determinants of every non-key attribute are superkeys.

Which is fine when you're comfortable with normalisation and know what you're doing. The OP however is just learning it and doing an academic exercise.

Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

We walk in the dark places no others will enter
We stand on the bridge and no one may pass

OCTom SSChampion Points: 11785 More actions · Answer 12

sqlvogel (8/6/2014)
pietlinden (8/5/2014)
How can you get to 3NF if you don't go through 1NF and 2NF first?
Very easily, you just need to ensure that the non-trivial determinants of every non-key attribute are superkeys. Outside of an academic exercise I'm surprised if anyone would go through the trouble of creating a table design that satisifies 1NF but not 2NF and then refine it to make it satisfy 2NF and then refine it again to make it 3NF. I've certainly never bothered with such exercises outside the classroom.
2NF and 3NF are of mostly historical or academic importance anyway. Most of the time it makes sense to design to Boyce-Codd / 5th Normal Form and don't concern yourself with 3NF except in cases where you need to denormalize in order to enforce certain business rules.

Although it moves very quickly, I still think in terms of 1st, 2nd and so forth. That way I know I have approached it correctly. Only with the simplest databases would I be comfortable with moving directly to BCNF. And, even then, I think my mind would still go through the earlier stages.

Tom

OCTom SSChampion Points: 11785 More actions · Answer 13

For the OP:

Here is a link with a straightforward explanation of the normal forms.

http://databases.about.com/od/specificproducts/a/normalization.htm

You should be able to create the 1st and 2nd normal forms from that explanation.

Tom

sqlvogel SSCrazy Eights Points: 9526 More actions · Answer 14

OCTom (8/6/2014)
For the OP:
Here is a link with a straightforward explanation of the normal forms.
http://databases.about.com/od/specificproducts/a/normalization.htm
You should be able to create the 1st and 2nd normal forms from that explanation.
Tom

"Straightforward" but also completely WRONG. Ignore it. Don't waste time reading anything on about.com.