Core Data search by word - ios

Question

I have a Core Data object Contact
Contact
=======
fullName
I'm using a NSFetchedResultsController to show a list of contacts.
I now want to add search option that behave as follow:
If user search for the string "da", the results should be:
Aaron David
Bert Daniels
Dana
John David
So the search result is alphabetic sorted strings that has a word starting with "da"
I remember watching a WWDC session showing how to create a Word object and store each word independently, but I'm trying to avoid this approach.
So my question is, can I do such a search with my current model structure and some predicate magic, or I must store the fullName as separate words?

Answer 1

This is what I do:
NSMutableArray *predicateArray = [NSMutableArray array];
if(searchString.length)
{
for (NSString* searchStringPart in [searchString componentsSeparatedByString:#" "])
{
if([searchStringPart length] > 0)
{
[predicateArray addObject:[NSPredicate predicateWithFormat:#"name CONTAINS[cd] %#", searchStringPart]];
}
}
filterPredicate = [NSCompoundPredicate andPredicateWithSubpredicates:#[filterPredicate, [NSCompoundPredicate andPredicateWithSubpredicates:predicateArray]]];
}
And for sorting:
NSSortDescriptor *sort = [[[NSSortDescriptor alloc] initWithKey:#"name" ascending:YES] autorelease];
NSArray* sortDescriptors = #[sort];
....
[fetchRequest setSortDescriptors:sortDescriptors];

Answer 2

You need to use predicate for filtered word by name in your array. Use below:-
//Assuming you have store the name in one array
NSArray *names=#[#"Aaron David",#"Bert Daniels",#"Dana",#"John David"];
//Now use contains in predicate for filtered words
//On the basis of search string it will filtered accordingly. lets Say yourStringValue=#"on"
NSPredicate *pd=[NSPredicate predicateWithFormat:#"self CONTAINS[CD] %#",yourStringValue];
NSArray *ar=[names filteredArrayUsingPredicate:pd];
NSLog(#"%#",ar);
Output:-
"Aaron David"