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Hello,

I have a entity in my core datamodell, "Tours". Tours has a attribute called "creationDate". In my iphone up, I want the tours to be seen in an table view, ordered by creationDate. This works fine. But now I want to go into master/detail. That is, I want to see in the master table view all Year/Month combinations from my tours entity. So, if I had two tours in september 2009, they will only show as one item:"9-2009". One level later, I will show the tours for september 2009.

In Sql it would be simple for me to get a result with unique Year/Month entries using a computed column and a group clause. What is the approach in core data. I think, I need @distinctUnionOfObjects. But how do I tell core data to compute a column, on which I will refer with a distinct operation?

Thanks a lot for your help.

Klaus-Dieter