How to decipher entity relationships in a Physical Data Model given the corresponding Logical Data Model 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?
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


PARTY is explicited
Segment Group Cd is exported as part of the identifying relationship (a solid line)
the verbs sentences are more verbose




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 MRKT_SGMNT and MRKT_SGMNT_GROUP entities
is incomplete - it's missing Party_Sgmnt_End_Dttm
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.