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This linking fact-table/view ties questions/answers to surveys, such that a single question/answer pair may be linked to an entire survey via an SSAS many-to-many relationship.
Why is this useful? Well, say a survey has demographic questions in addition to the normal questions one would associate with a survey. The demographic questions, or rather the question-answer pairs, actually apply to the subject responding to the survey. If, for example, a respondent says he is 'male' when asked his gender. The gender is really a property of the subject. And we may want to know how male subjects, as a group, responded to other questions. In this case, we want to set up a many-to-one relationship between each question answered by the respondent and the response to the gender question. And of course, since many subjects will have answered the gender question, the relationship in the opposite direction is one to many as well, meaning that the relationship in general is many-to-many. Hence this table.
This table should not normally be queried by users. It is solely used to set up the many-to-many relationship in analysis services. SQL experts might make use of it, though, in the relational database.
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