database

design

detailed design of attributes

In this section of the design I will consider what customisations should be made, decide what properties the attributes of each entity should have and justify the choices made.

the CD entity...

Below is a table showing the detailed layout of the CD entity's field properties:

Name of field Data type Field Size Choice field? Should it be indexed?
CD Number Text 10 No Yes; it is the (PK)
CD_Title Text 30 No No
Artist Text 30 No No

I chose Text for each of the fields because each contained both numbers and text.

the Order entity...

Below is a table showing the detailed layout of the Order entity's field properties:

Name of field Data type Field Size/Format Choice field? Should it be indexed?
Order Number Text 9 No Yes; it is the (PK)
CD Number Text 10 No Yes; it is the (FK)
Order Date Date/Time General Date No No
NewCust_Title Text 20 Yes: Mr, Mrs, Miss and Ms. No
First Name Text 30 No No
Last Name Text 30 No No
Address Line 1 Text 40 No No
Town Text 40 No No
County Text 30 No No
Post Code Text 7 No No
Card Type Text 20 Yes: Socket, Mister Card, Francard, Armenian Express and VISTA. No
Card Number Text 13 No No
Expiry Date Date/Time General Date No No

I chose Text for Order Number and CD Number because they contain both numbers and text. I chose General Date for the Order Date and Expiry Date fields because the dates listed in the data set don't meet the requirements for the Short Date format in Access. There are two choice fields because the values listed are the only ones present in the data set.

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database

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