ios - CoreData: Get the number of distinct elements -


i want number of distinct elements grouped value can have in coredata. equivalent select count(select price in glasses group price price!=null);

so far tried (i use magical record).

nsfetchrequest *fetchrequest = [glasses fetchrequest]; fetchrequest.predicate = [nspredicate predicatewithformat:@"price!=nil"]; fetchrequest.resulttype = nsdictionaryresulttype; fetchrequest.propertiestogroupby = @[@"price"]; fetchrequest.propertiestofetch = @[@"price"]; nsarray *results = [glasses mr_executefetchrequest:fetchrequest]

by calling results.count can correct information.

is there way retrieve count without fetching values ?


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