Results 1 to 1 of 1

Thread: ER Diagram!!

  1. #1
    Join Date
    Sep 2003
    Posts
    1

    Unhappy ER Diagram!!

    I need someone to advise me on my ER diagram.

    I learnt about ER models sometime ago and now I need to do it for one of my sch proj (but cannot recall much)...

    I need to design a webportal with a few functionalities in it..

    This is one of the specification:
    Auction
    -Members can view either by type, or all available items at once. Sort by type,brand, bid number (i.e. “HOT”), top bid, start date (i.e. “NEW”), and closing date
    -Members can post items for bidding
    -Members can upload the picture files of the items for bidding
    -Members can bid for available items
    -Members can remove items from auction (only for owners of the item or
    administrators)
    -Create “Category Type” (top-level) and “Category” (second-level)
    -Remove “Category Type” and “Category”
    -Remove current auction item
    -Access log of Past and Currently available items
    -Clear log of Archived items
    -Access log of Past and Current bids
    -Clear log of Archived bids

    I also need to include shopping cart, but my problem is: I'm not very sure how to link the shopping cart entity with an entity named transaction(for payment and delivery of products user purchase).

    These are what I wrote:
    shopping_cart
    -purchase_id**
    -quantity
    -cart_id

    transaction
    -transaction_id
    -cardholderName
    -creditcardNo
    -creditcardType
    -expiryDate
    -purchase_id
    -deliveryAddress
    -deliveryDate
    -purchaseDate**

    (**I don't where to put this attributes.)

    auction_item
    -category
    -sub-category
    -itemName
    -startDate
    -closingDate
    -topBid
    -startBid

    Question is:
    1)Are the attributes I identify appropriate?
    2)How shld I link shopping_cart & transaction, so that the transaction entity knows what products the user adds into its cart? Using the cart_id?
    3)Where shld be my category or sub-category be? Shld they be another entity? because there might be a lot of category and sub-category. Or shld they be just an attribute?

    Sorry for the long question..
    Hope someone can solve my problem..

    Thx Thx..
    Last edited by Piglet; 09-08-03 at 12:31.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •