Fact dimension relationships

If you build a dimension directly off a fact table (a fact dimension), when you add it to your cube and set the relationship between that dimension and the fact table you have a choice about the type of relationship you can use: you can use either a Fact relationship type or a Regular relationship type. I've always used Fact relationships but never known whether there was anything special about them - there was in some of the early Yukon betas but the functionality got dropped before RTM.

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