Tim Stevens wrote:
>>Ok that fair enough but begs some questions
>>1. how do I know it is optional?
>>
>>
>
>The clues are that they are not always set, the enumeration is
>limited and the cardinality of the child link is 0..*.
>
>This may sound weak, but it is like many bits of the data model to take a
>random example: Experiment.sampleVolume - there will be a value but it
>needn't be recorded. Things are just filled in by the user or application
>as things are discovered or when they are needed.
>
>T.
>
>
>
Many Thanks
that all makes sense now. Obviously haven't been that subtle enough
(yet) though I guess I will learn to be ;-)
regards
gary
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--
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Dr Gary Thompson
Astbury Centre for Structural Molecular Biology,
University of Leeds, Astbury Building,
Leeds, LS2 9JT, West-Yorkshire, UK Tel. +44-113-3433024
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