I've been having difficulty coming up with an HQL query the does something which seems like it should be very simple.

I need to select a value based on whether or not it is null. For example, let's say I have a table with userrating and overrideRating columns, where overrideRating may (and in most cases is) null.

I want overrideRating to override userrating, and sort by that value. I was able to do this in SQL as follows:

How would I express this in HQL? I don't need to have my hibernate properties mapped to this computed value. I just want to sort by this computed value.