Requirements
These were collected from a meeting we held with Larsson, Abhi, Mike, Brian, and Thaneer, and from a follow-up interview with Dan.
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Other possibilities listed at the end of this document
This seems best given Dwayne's comments below... manage external IDs separately, and in a transaction, mark when they are used and add them as an attribute to the AccountSubStudies table record, which is a true associative table.
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