Predicate search in core data causes SIGABRT on second time through. NSBetweenPredicateOperatorType

问题

I am seeing a really strange behavior in core data. I am doing a search for locations in core data (data store type is SQLite). The query is to look for location objects within a specific area. I am implementing the search as a between predicate.

NSExpression *lhs = [NSExpression expressionForKeyPath:keyPath];
NSExpression *rhs = [NSExpression expressionForVariable:@"MIN_MAX"];

NSPredicate *predicateTemplate = 
    [NSComparisonPredicate predicateWithLeftExpression:lhs       
                                       rightExpression:rhs
                                            modifier:NSDirectPredicateModifier
                                                 type:NSBetweenPredicateOperatorType
                                              options:0];

NSPredicate *predicate = [predicateTemplate predicateWithSubstitutionVariables:
                          [NSDictionary dictionaryWithObject:expressionArray forKey:@"MIN_MAX"]];

where expressions array is an array of 2 object, min in index 0, and max in index 1. Each object in the array is an NSConstantValueExpression, defined as :

NSExpression *ex = [NSExpression expressionForConstantValue : numberValue]

I am using the predicate in a NSFetchedResultsController, and the first time though works exactly as I expect. The final predicate is something like this:

NSFetchRequest: 0x7394360 (entity: Location; predicate: (longitude BETWEEN {-122.0767937067412, -121.7137663065599} AND latitude BETWEEN {37.16973380897733, 37.45968675392614} ); sortDescriptors: (("(name, ascending, compare:)")); limit: 20; type: NSManagedObjectResultType; )

And I get the results I want.

The second time this code is run (by pushing a second view on top, and closing that view. This causes the view to reload). The system crashes, with this error message.

-[NSConstantValueExpression compare:]: unrecognized selector sent to instance 0x71bbea0 2011-04-22 10:54:11.742 Wines[13667:207] Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSConstantValueExpression compare:]: unrecognized selector sent to instance 0x71bbea0'*

Any suggestions?

Full stack below.

Thanks,

    *** Call stack at first throw:
(
    0   CoreFoundation                      0x02f0bb99 __exceptionPreprocess + 185
    1   libobjc.A.dylib                     0x0305b40e objc_exception_throw + 47
    2   CoreFoundation                      0x02f0d6ab -[NSObject(NSObject) doesNotRecognizeSelector:] + 187
    3   CoreFoundation                      0x02e7d2b6 ___forwarding___ + 966
    4   CoreFoundation                      0x02e7ce72 _CF_forwarding_prep_0 + 50
    5   Foundation                          0x002dd909 -[NSBetweenPredicateOperator performPrimitiveOperationUsingObject:andObject:] + 317
    6   Foundation                          0x0020aee4 -[NSComparisonPredicate evaluateWithObject:substitutionVariables:] + 306
    7   Foundation                          0x00210ead -[NSCompoundPredicateOperator evaluatePredicates:withObject:substitutionVariables:] + 292
    8   Foundation                          0x00210d57 -[NSCompoundPredicate evaluateWithObject:substitutionVariables:] + 254
    9   Foundation                          0x0020adac -[NSPredicate evaluateWithObject:] + 49
    10  CoreData                            0x0252ae08 -[NSManagedObjectContext executeFetchRequest:error:] + 1752
    11  Wines                               0x00021b27 -[MOListViewController listFRC] + 1034
    12  Wines                               0x000bb1e8 -[MOLocationSelectableListViewController numberOfSectionsInTableView:] + 36
    13  UIKit                               0x0061849c -[UITableViewRowData(UITableViewRowDataPrivate) _updateNumSections] + 111
    14  UIKit                               0x00618228 -[UITableViewRowData invalidateAllSections] + 66
    15  UIKit                               0x004d2880 -[UITableView(_UITableViewPrivate) _updateRowData] + 113
    16  UIKit                               0x004cbe9c -[UITableView noteNumberOfRowsChanged] + 105
    17  UIKit                               0x004d853c -[UITableView reloadData] + 773
    18  UIKit                               0x004d5724 -[UITableView layoutSubviews] + 42
    19  QuartzCore                          0x02a22481 -[CALayer layoutSublayers] + 177
    20  QuartzCore                          0x02a221b1 CALayerLayoutIfNeeded + 220
    21  QuartzCore                          0x02a220bd -[CALayer layoutIfNeeded] + 111
    22  UIKit                               0x0050c94b -[UIViewController window:willAnimateRotationToInterfaceOrientation:duration:] + 567
    23  UIKit                               0x004889bd -[UIWindow _setRotatableClient:toOrientation:duration:force:] + 4159
    24  UIKit                               0x006fa67b -[UIWindowController transition:fromViewController:toViewController:target:didEndSelector:] + 768
    25  UIKit                               0x0050f10d -[UIViewController presentModalViewController:withTransition:] + 2937
    26  UIKit                               0x00508402 -[UIViewController _tryRecursivelyPresentModalViewController:withTransition:] + 134
    27  UIKit                               0x005083c6 -[UIViewController _tryRecursivelyPresentModalViewController:withTransition:] + 74
    28  UIKit                               0x0050e8e6 -[UIViewController presentModalViewController:withTransition:] + 850
    29  Wines                               0x0002d7a9 -[MOViewController didSelectToOneSelectOneAtIndexPath:] + 2195
    30  Wines                               0x0002e843 -[MOViewController tableView:didSelectRowAtIndexPath:] + 4219
    31  Wines                               0x0005544f -[MOPriceViewController tableView:didSelectRowAtIndexPath:] + 1509
    32  UIKit                               0x004d4a48 -[UITableView _selectRowAtIndexPath:animated:scrollPosition:notifyDelegate:] + 1140
    33  UIKit                               0x004cb32e -[UITableView _userSelectRowAtIndexPath:] + 219
    34  Foundation                          0x001e021a __NSFireDelayedPerform + 441
    35  CoreFoundation                      0x02eecf73 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 19
    36  CoreFoundation                      0x02eee5b4 __CFRunLoopDoTimer + 1364
    37  CoreFoundation                      0x02e4add9 __CFRunLoopRun + 1817
    38  CoreFoundation                      0x02e4a350 CFRunLoopRunSpecific + 208
    39  CoreFoundation                      0x02e4a271 CFRunLoopRunInMode + 97
    40  GraphicsServices                    0x035bf00c GSEventRunModal + 217
    41  GraphicsServices                    0x035bf0d1 GSEventRun + 115
    42  UIKit                               0x0046faf2 UIApplicationMain + 1160
    43  Wines                               0x00002814 main + 102
    44  Wines                               0x000027a5 start + 53
)
terminate called after throwing an instance of 'NSException'
Program received signal:  “SIGABRT”.

回答1:

here ya go...

BETWEEN operations are aggregate operations, and aggregate operations are not supported by Core Data. You'll need to turn this into:

NSPredicate *p = [NSPredicate predicateWithFormat:@"%K >= %@ AND %K <= %@", keyPath, lowerBound, keyPath, upperBound];

来源：https://stackoverflow.com/questions/5758730/predicate-search-in-core-data-causes-sigabrt-on-second-time-through-nsbetweenpr