Can someone use the entity relationships in this Logical Data Model (LDM):
to explain the entity relationships in this Physical Data Model (PDM):
- and how to specify the foreign keys in the PDM?
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I'm not sure that I understood your question...
That said, lemme try to help you.
I undestand the model represents the categorization of 'parties' as begin part of 'segments'. These categorizations are mutable and have to be traceable in time.
Let me humbly present what I think is a more complete LDM, where
Segment Group Cdis exported as part of the identifying relationship (a solid line)
From this LDM, the straightest derived 3NF (3rd Normal Form) PDM should be (
PARTY entity not shown):
The PDM you posted:
is denormalized -
MRKT_SGMNT_GROUP comprises both
is incomplete - it's missing
states redundant relationships - the two relationships are the same
or, more formalistically, states an incorrect relationship - the identifying relationship (the one represented as a solid line) yelds both key properties from
MRKT_SEGMNT_GROUP as key properties to
PARTY_SGMNT_HIST, which aren't - just
Sgmnt_Id has been derived as part of the PK
With the denormalization presented, the PDM ought to be, with the missing property marked in bold red:
Did this serve as any help? Hope so...
Regards, Marcus Vinicius.