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Introducing the OMOP CDM ER diagram challenge! Submissions due 13Dec2022

I would say that the ERD diagrams that we did as an exercise are actually physical models. Most of them targeted a very specific database platform - PostgreS - and were just a result of a reverse engineering the existing schema and then making it look good. Logical models do not have a notion of a Primary/Foreign key - they show named entities, key platform independent attributes and relationships between entities.

I would also say that it is wrong to say that the same logical model (OMOP CDM) will have the same ERD and physical implementation for all databases. So yes - you are correct that each database would have to have an ERD implementation of the logical model. They will be similar but not the same

Interesting. Two different answers! :slight_smile: @Christian_Reich what do you say? Are these ERDs logical or physical?

@gregk is correct, I misspoke.

So if the ERDs are physical then they are dbms specific, right?

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