Databases
StackOverflow2013
Postsdbo
POSimple NSPredicate @"1 == 0" not filtering fetched results?
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POSimple NSPredicate @"1 == 0" not filtering fetched results?
    primarykey
    data
    text
    <p>What is wrong with this code?</p> <p>I know this is a silly predicate. But it's just to show that if this was working, it should be filter everything out, right?</p> <p>Somehow, it's not. I'm getting every Month object in my DB, when I should be getting none.</p> <p>I guess this tells me that the problem might not be in the predicate?</p> <pre><code>NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init]; NSEntityDescription *entity = [NSEntityDescription entityForName:@"Month" inManagedObjectContext:managedObjectContext]; [fetchRequest setEntity:entity]; [fetchRequest setPredicate: [NSPredicate predicateWithFormat:@"1 == 0"]]; NSSortDescriptor *sortDescriptor1 = [[NSSortDescriptor alloc] initWithKey:@"month_" ascending:YES]; NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor1, nil]; [fetchRequest setSortDescriptors:sortDescriptors]; [fetchRequest setFetchBatchSize:20]; NSFetchedResultsController *theFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:managedObjectContext sectionNameKeyPath:@"month_" cacheName:@"Root"]; - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { return [[_fetchedResultsController sections] count]; } </code></pre> <p>What I actually wanted to do is,</p> <pre><code>[NSPredicate predicateWithFormat:@"year.year_ == %d", year] </code></pre> <p>And I also tried this,</p> <pre><code>[NSPredicate predicateWithFormat:@"month_ == %d", 1] </code></pre> <p>Just to see if it works. But nothing.</p> <p>edit:</p> <p>At this point, no matter what predicate I set, as long it's a valid, well formatted predicate. It doesn't complaint, and get's me all objects. It's just not filtering anything.</p> <p>I'm pretty much using boiler plate code from Apple's documentation.</p> <p>Can anyone help me figure this out?</p> <p>Thank you!</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USnmdias
    1. USnmdias
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POSimple NSPredicate @"1 == 0" not filtering fetched results?
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. POSimple NSPredicate @"1 == 0" not filtering fetched results?
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. POSimple NSPredicate @"1 == 0" not filtering fetched results?
      1. This table or related slice is empty.
      1. VTDownMod
    1. COBecause `1 == 0` is always false, you'll have no results matching this condition.
      singulars
      1. POSimple NSPredicate @"1 == 0" not filtering fetched results?
      1. This table or related slice is empty.
    2. COThat's exactly my problem. It's returning everything, no matter what predicate I set. 1 == 0, should give me NO results whatsoever. But somehow, it gets me ALL objects.
      singulars
      1. POSimple NSPredicate @"1 == 0" not filtering fetched results?
      1. USnmdias
    3. COTry deleting your cache. Also, if you switched to iOS6 already, there are several bugs with predicates and limits in `NSFetchedResultsController` right now.
      singulars
      1. POSimple NSPredicate @"1 == 0" not filtering fetched results?
      1. USKyr Dunenkoff
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload