oracle - SQL Database, ERD, crows foot notation, -

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i have erd diagram have crows foot on customer going dotted line straight line membership. mean members must customers , customers may hold membership? regards

i'm not sure whether understood correctly. have like

customer >- - - - - ----membership

correct?

if that's case means membership can owned multiple customers, it's compulsory customer have membership (mandatory relationship - if optional you'd have 0 @ membership table line), , dotted line means it's non-identifying 1 (i.e: foreign key not part of members primary key - or customer not identified membership)


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