attributes - Database - Entity relationship diagram -

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presentations:

• details of speakers - speakers, topics, times, contact details, special requirements (if any) e.g. data projection, audio, powerpoint version

• details of chairs (your model should able cope more 1 “n” number) each presentation session, there chairpersons chair presentations; changeover @ refreshment breaks, need know session each do; contact details.

with info above, can fit both speakers , chairs attributes under 1 entity called 'presentation' or should create 2 new entities - 1 speaker , 1 chairs?

based on question, seems want more entities those. depends on if there other specifications , data related each of entities.

anyways, here's 1 possible idea: presentations entity persons entity (name , contact details) speaker_for relationship (persons presentations) chairperson_for relationship (persons presentations)

this way can speak @ many presentations or chair many presentations, , can query that. person speak @ 1 presentation , chair another. can have speakers entity , chairs entity, similar seems unnecessary me.

like said, adapt liking , conforming other specs.


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