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Can someone check this ER design please

From: Simon Kearns <skearns_at_iconz.co.nz>
Date: Fri, 9 Mar 2001 13:01:39 +1300
Message-ID: <3aa81fd7@news.nz.asiaonline.net>

I am building a DB for recording Land Shareholding Transfers. Shares are transferred when someone dies to their relatives. i.e. split amongst one or more beneficiaries
My design works but I'm not confident that it is completely correct. 1. The big issue that concerns/confuses me is that:  "Owners transfer shares to other Owners" i.e. therefore, an Owner is at different times both a Sharegiver and a Sharegetter.
I solve this problem by a JOIN on tblOwner as tblSharegetter 2. The other issue is questions of whether the DB tables have associative or attributive qualities ( and whether it matters all that much!)

Here's the cutdown ERD

tblOwner
|OwnerID(pk)|

has one to many relationship with
(one owner may be a sharegiver in zero or more TransferEvents)

tblTransferEvent
|EventID(pk)|OwnerID(fk)|

has one to many relationship with
(one TransferEvent may include zero or more TransferCredits)

tblTransferCredit
|CreditId(pk)|EventID(fk)|OwnerID as SharegetterID(fk)| --it's this part
which i'm unsure about!!

Thanks
Simon Received on Thu Mar 08 2001 - 18:01:39 CST

Original text of this message

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