I am working on a member search for an intranet site.  And I would like to offer dropdowns populated with values people have entered for certain properties.

For example each member has a university property with the name of the institution they go to.  I would like to populate a drop down with all the unique values members have set for this property so I get a list of all the universities members go to.

I was thinking of using examine for this.  But don't know how to write the query.

How do I do a "not empty" using the fluent API.  And can you also do a distinct using it or will I need to filter the results to get the unique values.

This is what I have so far, obviously this finds those with the university property not set when I want the opposite.

filter = criteria.Field("university", string.Empty).And().OrderBy("university").Compile();