title: How to define structure in a tag-based organization?
body: <p>[former title: Is there a way to force a relationship structure on a tag-based organizational methodology?]</p>
  
  <p>I have some entities, and they have a series of attributes. Some of the attributes affect what other attributes the entity can have, many of the attributes are organized into groups, and occasionally entities are requited to have certain numbers of attributes from certain groups, or possibly a range of attributes from certain groups.</p>
  
  <p>Is there a way to model these sorts of tag-to-tag relationships, such as requirement, grouping, exclusion, etc. using a database, or is this only possible with programmed "business rules"? Ideally, I would like the possible tags and their relationships to be easily configurable, and hence highly flexible.</p>
  
  <p>One of the ways I have considered is to have the tags and possible relationships, and then you get a tag-tag-applied relationship sort of table, but this seems like a rather brittle approach.</p>
  
  <p>So, is this possible in a more rigorous fashion, and if so, how would I even begin to go about it?</p>