NHibernate - use WHERE clause on one-to-one mapping

Is it possible to somehow restrict a one-to-one mapping with 开发者_JAVA技巧a constraint other than property ref? Ideally, something along the lines of the class definition, for example, where you can add where="Condition=Value".

Thanks

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You can use nhibernate filters for this: http://nhibernate.info/blogs/nhibernate/archive/2009/05/04/nhibernate-filters.aspx