Second Normal form

For tutorial

Second Normal Form

• Remove part key dependencies– Only applies to forms that are in first normal

form and have a compound key• i.e. more than one field in the key.

– Remove the fields that are dependent on the part key and borrow the part key, to become the primary key of the new form. This form will then be a master form for the new form.

TNF Exercise.

• Objective.– To practise the normalisation technique and to

produce a set of optimised relations from the normalisation of six documents.

• Method.– 1. Apply the rules of normalisation to the

supplied documents.– 2. Note the business rules.

Supplied Documents

• Product Sales Report

• Wellingtons Invoice

• Product Stock Report

• Sales Executive report

• New Product / Amendment

• Customer Amendment

Business Rules

• Product Code is not unique – each may have a number of pack sizes.

• Some Customers are allowed a discount. Each item has a Standard Price and up to 3 discount prices. A customer entitled to a discount has a single discount code A, B, C and will be charged the appropriate A, B or C price for all Products he orders.

• At any Warehouse, a Product is only stocked in one bin. The bin code may be considered unique to a warehouse.

• A customer deals with one, and only one, Sales Executive.

Product W10190 DescriptionPack Size 10' Roll

Invoice Date Customer No. Name Quantity Line Value1468/02 2/2/2002 71698 Simons Health Hydro 2 € 12.601472/02 2/2/2002 32114 T White 3 € 18.901497/02 2/4/2002 10068 Int. Del. Limited 6 € 37.801501/02 2/9/2002 31724 Thumbscrew Ass. 3 € 18.901506/02 3/10/2002 21641 Hypo Explosives 15 € 94.50

PRODUCT SALES REPORT

Elastic Bandage

Product Sales Report

Unnormalised Form

• Product Code + PackSize + ProductDescription + {InvoiceNumber + InvoiceDate + CustomerNumber + CustomerName + InvoiceQuantity + LineValue}

First Normal Form

• ProductCode+PackSize + ProductDescription

• (ProductCode + PackSize)* + InvoiceNumber + InvoiceDate + CustomerNumber + CustomerName + InvoiceQuantity + LineValue

First Normal form Product Sales Report

• The product description is dependent only on the ProductCode, so – ProductCode+PackSize + ProductDescription

• Becomes– ProductCode*+PackSize– ProductCode + ProductDescription

2nf Product Sales Report

• and– (ProductCode + PackSize)* + InvoiceNumber +

InvoiceDate + CustomerNumber + CustomerName + InvoiceQuantity + LineValue

• becomes– (ProductCode + PackSize)* + InvoiceNumber* +

InvoiceQuantity + LineValue

• And– InvoiceNumber + InvoiceDate + CustomerNumber +

CustomerName

Invoice DateCustomer No. Name

1468/02 02/02/2002 71698Simons Health Hydro

1472/02 02/02/2002 32114 T White

1497/02 02/04/2002 10068 Int. Del. Limited

1501/02 02/09/2002 31724 Thumbscrew Ass.1506/02 03/10/2002 21641 Hypo Explosives

2nd Normal form Product Sales Report

Product Pack SizeW10190 10' Roll

Product DescriptionW10190 1468/02

Product Pack Size Invoice QuantityLine Value

W10190 10' Roll 1468/02 2 € 12.60W10190 10' Roll 1472/02 3 € 18.90W10190 10' Roll 1497/02 6 € 37.80W10190 10' Roll 1501/02 3 € 18.90

InvoiceInvoice Number 1468/02 Date 02/02/2002Customer 71698Name and Address Simon's Health Hydro

Warwick HouseBounds GreenLondon N11

Product DescriptionProduct Code

Pack Size

Standard Price

Discount Code

Discount Price Qty Line Value

Absorbant Gauze W10076 3x4 € 4.00 N € 4.00 15 € 60.00Zinc Oxide Plaster W10064 2" Roll € 12.40 N € 12.40 1 € 12.40Elastic Bandages W10190 10' Roll € 6.30 N € 6.30 2 € 12.60Soluble Aspirin W10941 500 € 10.00 N € 10.00 4 € 40.00Paracetamol W10918 250 € 9.20 N € 9.20 3 € 27.60

€ 152.60

INVOICE

Unnormalised Form

• InvoiceNumber + InvoiceDate + CustomerNumber + CustomerName + CustomerInvoiceAddr + {ProductDescription + ProductCode + PackSize + StandardPrice + DiscountCode + DiscountPrice + InvoiceQuantity + LineValue} + InvoiceValue

First Normal Form

• InvoiceNumber + InvoiceDate + CustomerNumber + CustomerName + CustomerInvoiceAddr + DiscountCode

• InvoiceNumber* + ProductCode + PackSize + ProductDescription + StandardPrice + DiscountPrice + InvoiceQuantity

Second Normal Form

• InvoiceNumber + InvoiceDate + CustomerNumber + CustomerName + CustomerInvoiceAddr + DiscountCode

• InvoiceNumber* + ProductCode + PackSize + DiscountPrice + InvoiceQuantity

• ProductCode + ProductDescription

• ProductCode + PackSize + StandardPrice

Product W10941Pack Size 500

Warehouse Stock Qty. Bin Code No. Ordered YTD1 930 71 2802 500 14 7643 1324 38 3204 2271 61 43625 0 94 31716 60 8 3207 0 6 48918 320 14 4016

Totals 5405 18124

PRODUCT STOCK REPORT

Product Stock Report

Unnormalised Form

• ProductCode + PackSize + Warehouse + StockQuantity + BinCode + NoOrdYTD + StockQuantityTotal + NoOrdYTDTotal

First Normal Form

• ProductCode + PackSize + StockQuantityTotal + NoOrdYTDTotal

• (ProductCode + PackSize)* + Warehouse + StockQuantity + BinCode + NoOrdYTD

2nd Normal Form

• ProductCode + PackSize

• (ProductCode + PackSize)* + Warehouse + StockQuantity + BinCode + NoOrdYTD– remains the same

Sales Executive 32

Customer Orders YTD Value OrdersDiscount

Code61784 110 € 560.00 A31477 212 € 1,028.00 A61344 104 € 442.00 A21242 38 € 271.00 B31687 73 € 340.00 B41279 30 € 128.00 B81311 21 € 90.00 C11600 87 € 1,008.00 N

Sales Executive Total 675 € 3,867.00

SALES EXECUTIVE REPORT

Sales Executive Report

Unnormalised Form

• SalesExecutive + CustomerNumber + OrdersYTD + ValueOrders + DiscountCode + OrdersYTDTotal + ValueOrdersTotal

First Normal Form

• SalesExecutive + OrdersYTDTotal + ValueOrdersTotal

• CustomerNumber + SalesExecutive* + OrdersYTD + ValueOrders + DiscountCode

• No compound keys, so no change for 2NF.

*P_____

Product (W________) Description (________________________)

Pack Size (________) Prescription Indicator(_)

Unit Quantity (___) UK Drug Reg. No. (______)

Minimum Stock (_____) Discount Prices A ____.__B ____.__C ____.__

* Key 01 New Product02 Deletion03 Amendment

Product

Pack Size

NEW PRODUCT / AMENDMENT

Must be completed

New Product / Amendment

Unnormalised Form

• ProductCode + PackSize + ProductDescription + PrescriptionIndicator + UnitQuantity + UKDrugRegNo + MinimumStock + DiscountCode + DiscountPrice

First Normal Form

• ProductCode + PackSize + ProductDescription + PrescriptionIndicator + UnitQuantity + UKDrugRegNo + MinimumStock

• ProductCode + PackSize + DiscountCode + DiscountPrice

• Product Description, Prescription Indicator and UKDrugRegNo only depends on Product Code

Second Normal Form

• ProductCode* + PackSize + UnitQuantity + MinimumStock

• ProductCode + ProductDescription + UKDrugRegNo + PrescriptionIndicator

• ProductCode + PackSize + DiscountCode + DiscountPrice

Customer AmendmentCustomer No. (________)Sales Executive (____) (__)

Name (____________________)Address (____________________)

(____________________)(____________________)(____________________)

Credit Limit (______) Bulk Pack Only (_)

Discount Code (__)*

Licensed Drug Vendor (_)

(____________________)(____________________)(____________________)(____________________)

* A, B, C, Default N.

Delivery Address (if different from above)

Preferred Customer

CUSTOMER AMENDMENT

Unnormalised Form

• CustomerNumber + SalesExecutive + PreferredCustomer + CustomerName + CustomerInvoiceAddr + CreditLimit + BulkPackOnly + DiscountCode + LicensedDrugVendor + CustomerDeliveryAddress