CoreData: Same predicate (IN) returns different fetched results after a Save operation
- by Jason Lee
I have code below:
NSArray *existedTasks = [[TaskBizDB sharedInstance] fetchTasksWatchedByMeOfProject:projectId];
[context save:&error];
existedTasks = [[TaskBizDB sharedInstance] fetchTasksWatchedByMeOfProject:projectId];
NSArray *allTasks = [[TaskBizDB sharedInstance] fetchTasksOfProject:projectId];
First line returns two objects;
Second line save the context;
Third line returns just one object, which is contained in the 'two objects' above;
And the last line returns 6 objects, containing the 'two objects'
returned at the first line.
The fetch interface works like below:
WXModel *model = [WXModel modelWithEntity:NSStringFromClass([WQPKTeamTask class])];
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"(%@ IN personWatchers) AND (projectId == %d)", currentLoginUser, projectId];
[model setPredicate:predicate];
NSArray *fetchedTasks = [model fetch];
if (fetchedTasks.count == 0) return nil;
return fetchedTasks;
What confused me is that, with the same fetch request, why return different results just after a save?
Here comes more detail:
The 'two objects' returned at the first line are:
<WQPKTeamTask: 0x1b92fcc0> (entity: WQPKTeamTask; id: 0x1b9300f0 <x-coredata://CFFD3F8B-E613-4DE8-85AA-4D6DD08E88C5/WQPKTeamTask/p9> ; data: {
projectId = 372004;
taskId = 338001;
personWatchers = (
"0xf0bf440 <x-coredata://CFFD3F8B-E613-4DE8-85AA-4D6DD08E88C5/WWPerson/p1>"
);
}
<WQPKTeamTask: 0xf3f6130> (entity: WQPKTeamTask; id: 0xf3cb8d0 <x-coredata://CFFD3F8B-E613-4DE8-85AA-4D6DD08E88C5/WQPKTeamTask/p11> ; data: {
projectId = 372004;
taskId = 340006;
personWatchers = (
"0xf0bf440 <x-coredata://CFFD3F8B-E613-4DE8-85AA-4D6DD08E88C5/WWPerson/p1>"
);
}
And the only one object returned at third line is:
<WQPKTeamTask: 0x1b92fcc0> (entity: WQPKTeamTask; id: 0x1b9300f0 <x-coredata://CFFD3F8B-E613-4DE8-85AA-4D6DD08E88C5/WQPKTeamTask/p9> ; data: {
projectId = 372004;
taskId = 338001;
personWatchers = (
"0xf0bf440 <x-coredata://CFFD3F8B-E613-4DE8-85AA-4D6DD08E88C5/WWPerson/p1>"
);
}
Printing description of allTasks:
<_PFArray 0xf30b9a0>(
<WQPKTeamTask: 0xf3ab9d0> (entity: WQPKTeamTask; id: 0xf3cda40 <x-coredata://CFFD3F8B-E613-4DE8-85AA-4D6DD08E88C5/WQPKTeamTask/p6> ; data: <fault>),
<WQPKTeamTask: 0xf315720> (entity: WQPKTeamTask; id: 0xf3c23a0 <x-coredata://CFFD3F8B-E613-4DE8-85AA-4D6DD08E88C5/WQPKTeamTask/p7> ; data: <fault>),
<WQPKTeamTask: 0xf3a1ed0> (entity: WQPKTeamTask; id: 0xf3cda30 <x-coredata://CFFD3F8B-E613-4DE8-85AA-4D6DD08E88C5/WQPKTeamTask/p8> ; data: <fault>),
<WQPKTeamTask: 0x1b92fcc0> (entity: WQPKTeamTask; id: 0x1b9300f0 <x-coredata://CFFD3F8B-E613-4DE8-85AA-4D6DD08E88C5/WQPKTeamTask/p9> ; data: {
projectId = 372004;
taskId = 338001;
personWatchers = (
"0xf0bf440 <x-coredata://CFFD3F8B-E613-4DE8-85AA-4D6DD08E88C5/WWPerson/p1>"
);
}),
<WQPKTeamTask: 0xf325e50> (entity: WQPKTeamTask; id: 0xf343820 <x-coredata://CFFD3F8B-E613-4DE8-85AA-4D6DD08E88C5/WQPKTeamTask/p10> ; data: <fault>),
<WQPKTeamTask: 0xf3f6130> (entity: WQPKTeamTask; id: 0xf3cb8d0 <x-coredata://CFFD3F8B-E613-4DE8-85AA-4D6DD08E88C5/WQPKTeamTask/p11> ; data: {
projectId = 372004;
taskId = 340006;
personWatchers = (
"0xf0bf440 <x-coredata://CFFD3F8B-E613-4DE8-85AA-4D6DD08E88C5/WWPerson/p1>"
);
})
)
UPDATE 1
If I call the same interface fetchTasksWatchedByMeOfProject: in:
#pragma mark - NSFetchedResultsController Delegate
- (void)controllerDidChangeContent:(NSFetchedResultsController *)controller
{
I will get 'two objects' as well.
UPDATE 2
I've tried:
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"(ANY personWatchers == %@) AND (projectId == %d)", currentLoginUser, projectId];
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"(ANY personWatchers.personId == %@) AND (projectId == %d)", currentLoginUserId, projectId];
Still the same result.
UPDATE 3
I've checked the save:&error, error is nil.
