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Posted by Tom on 10/10/05 20:13
Hi,
Do you guys know what's wrong with a one-to-one relationship?
The reason I want to make it like this is that at the very end of the chain,
the set of keys is huge. I want to limit the number of columns to be the
key. i.e. the [company] table has 1 column as the key. The [employee]
table will have 2 columns as the key.
e,g,
If I add a [sale] table to the [company]-[employee] relationship, the third
table
will have 3 columns as the key -- "company id", "employee id", and "sale
id".
(e.g.)
I have a company with many employees and computers. But instead of classify
all these, I just want to call all these as an entity. A company is an
entity. An employee is just another entity. etc.
So, instead of a one-to-many:
[company]---*[employee]---*[sale]
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*
[computer]
I make it one-to-one.
[entity]---*[entity]
If I want to know the name and address of the entity "employee", I will have
a 1-to-1 table [employee] to look up the information for this employee
entity.
[entity]---*[entity]
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[company]
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[employee]
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[computer]
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[sale]
--
> There is no answer.
> There has not been an answer.
> There will not be an answer.
> That IS the answer!
> And I am screwed.
> Deadline was due yesterday.
>
> There is no point to life.
> THAT IS THE POINT.
> And we are screwed.
> We will run out of oil soon.
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