fetching particular predicate from database - ios

Question

I have 4 CoreData database. Each actually having their own value. But it is too heavy and i would like to reduce it to 1 Database. So each time i want to pull information from the database, i can choose what to pull. I need to use NSPredicate to set the string that i want to pull izzit?
Do i set my NSPredicate like this?
NSString *value = #"Food";
NSString *wildcardedString = [NSString stringWithFormat:#"%#*", value];
[[NSPredicate predicateWithFormat:#"ANY places.type like %#", wildcardedString];
and how do i bind the NSPredicate with the fetch request sequence?
this is my fetchedResultsController
- (NSFetchedResultsController *)fetchedResultsController {
if (fetchedResultsController != nil)
{
return fetchedResultsController;
}
CoreDataMelakaAppDelegate *appDelegate = (CoreDataMelakaAppDelegate *)[[UIApplication sharedApplication] delegate];
NSManagedObjectContext *context = [appDelegate managedObjectContext];
NSFetchRequest *fetchRequest = [[[NSFetchRequest alloc] init] autorelease];
[fetchRequest setEntity:[NSEntityDescription entityForName:#"WhereTo" inManagedObjectContext:context]];
NSSortDescriptor *sortDescriptor = [[[NSSortDescriptor alloc] initWithKey:#"name" ascending:YES] autorelease];
NSArray *sortDescriptors = [[[NSArray alloc] initWithObjects:sortDescriptor, nil] autorelease];
[fetchRequest setSortDescriptors:sortDescriptors];
// NSPredicate *pred = [NSPredicate predicateWithFormat:#"(name = %#)", wher.name];
//[fetchRequest setPredicate:pred];
NSString *value = #"Nasi";
NSString *wildcardedString = [NSString stringWithFormat:#"%#*", value];
[[NSPredicate predicateWithFormat:#"ANY wher.name like %#", wildcardedString];
NSFetchedResultsController *aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:context sectionNameKeyPath:nil cacheName:#"Root"];
aFetchedResultsController.delegate = self;
self.fetchedResultsController = aFetchedResultsController;
[aFetchedResultsController release];
return fetchedResultsController;
}

Answer 1

When you alter the predicate of a fetch request used by a fetched results controller (FRC), you have to create a new fetched results controller.
Your code is fine logically but it only creates a FRC once with a predicate that compiles to:
ANY wher.name like Nasi*
... each time the FRC executes its fetch, it use that exact predicate.
If you want to use a flexible predicate, you will need to create a new FRC every time you change the predicate.