More information about the table An invoice may have more th

More information about the table: An invoice may have more than one product and the table uses a composite primary key.

INV_NUM (PK)

PROD_NUM (PK)

SALE_DATE

PROD_DESCRIPTION

VEND_CODE

VEND_NAME

NUMBER_SOLD

PROD_PRICE

211347

AA_E3422QW

6/25/1999

B&D Rotary sander, 6 in. disk

211

NeverFail, Inc.

2

$49.95

(10) Is the table in 1NF? Why or why not?

(10) Is it in 2NF? Why or why not?

(10) Is it in 3NF? Why or why not?

(5) How many tables do we need after normalization?

Solution

INV_NUM -----> SALE_DATE

INV_NUM -------> NUMBER_SOLD

PROD_NUM -----> PROD_DESCRIPTION

PROD_NUM ------> PROD_PRICE

VEND_CODE ------> VEND_NAME

All the non key attributes are not fully functionally dependent on the composite key . The non key attributes are partially dependent on the composite key. So the table is not in 2nd normal form .

INVOICE(INV_NUM,SALE_DATE,NUMBER_SOLD)

PRODUCT(PROD_NUM,PROD_DESCRIPTION,PROD_PRICE)

VENDOR(VEND_CODE,VEND_NAME)