I was just trying to explain that whereas systems analysts were traditionally trained in a rich variety of relationship including 1:0/1 and 1:1, the modern technical implementation will be 1-many (or two 1-manys if necessary) to physically implement everything from the logical analysis -- see CJ Date, An Introduction to Database Systems, somewhere in the 1980s if I remember correctly, which seemed "modern" back then anyway :)

update: to explain the 1:0or1, an example is employee -> employment details. On termination of contract, you might want to delete employment details but retain the employee header because the ex-employee still has pension rights being maintained in other tables. Later you might change your mind and just mark them deleted rather than physically delete them in which case it's a one-to-one but either way the physical implementation is still usually 1-many.

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^M Free your mind!

In reply to Re^5: How to implement set-style membership lists in my obejcts by Moron
in thread How to implement set-style membership lists in my obejcts by clinton

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