NSPredicate for nested sets

Question

Say we have A <-->> B <-->> C. We have multiple A entities, and C entities have an attribute called label. How can I find all A entities that contain C entities that contain @"1234"?

I saw this SUBQUERY in core data and it works great, but I'm basically trying to go one level deeper.

How could I achieve that?

thank you

The answer has been given by Dave DeLong. Here http://stackoverflow.com/questions/6890079/subquery-in-core-data/6890424#comment15997401_6890424 — zumzum, Aug 17 '12 at 03:21

score 0 · Accepted Answer · answered Aug 17 '12 at 17:28

The solution to this question was given by Dave DeLong.

I am pasting here the one line of code that shows the subquery that worked for me in case it can help somebody else.

NSPredicate * sp = [NSPredicate predicateWithFormat:@"SUBQUERY(catalogItemClasses, $b, ANY $b.catalogItems.label contains[cd] %@).@count > 0", searchText];

So here the structure I am dealing with is A <-->> B <-->> C. B entities are the "catalogItemClass" and C are the "catalogItem" entities. This allows me to query for A entities that are related to C entities that have labels that contain the string searchText in them.

Thanks Dave.

NSPredicate for nested sets

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