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<div class="PlainText">Hi Folks<br>
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I'm building an alias dbms. Multiple aliases can refer to the same person (genetics subject). I've two main entities: ID, an identifier; and an EquivalentIDset, which points to a set of aliased IDs. EquivalentIDset needs to be a separate entity, so it can have
attributes. One of those attributes is canonicalID, the primary ID (if any) among the set.
<br>
<br>
However, when I set canonicalID and scan through the IDs, I get a 'Cannot save cyclic chain' exception. Here's an (almost) freestanding extract of my code that generates the error:<br>
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What does the exception mean?<br>
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What's the best way to handle this? My thought is to not define canonicalID as an entity reference, but as a string equal to ID.identifier. But that would lose the dbms consistency benefits. Suggestions?<br>
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Thanks<br>
Arthur<br>
<br>
PS:<br>
$ pip show pony<br>
---<br>
Name: pony<br>
Version: 0.5.4<br>
Location: /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages<br>
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