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Core-Data: NSLog output does not show "fields"

I do not understand the NSLog output for the array returned by NSFetchRequest.

I read my database and put the contents into an array, iterate over the array and then output the contents to NSLog. I do not quite understand the output in the log file. Code below:

-(void)createXMLFeed{
    //Fetch details from the database.
    NSFetchRequest *request = [[NSFetchRequest alloc] init];
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Tabrss" inManagedObjectContext:managedObjectContext];
    [request setEntity:entity];
    NSError *error;
    self.stories = [[managedObjectContext executeFetchRequest:request error:&error] mutableCopy];
    //[request release];

    // Count the number of items in the array and display in the log.
    int arrayItemQuantity = [stories count];
    NSLog(@"Array Quantity: %d", arrayItemQuantity);

    // Loop through the array and display the contents.
    int i;
    for (i = 0; i < arrayItemQuantity; i++)
        NSLog (@"Element %i = %@", i, [stories objectAtIndex: i]);

    [stories release]; 

    // Update log file.
    NSLog(@"Database read and XML feed created.");
}

The contents of the log file:

2010-06-24 10:09:56.918 TAB RSS[998:207] Array Quantity: 15
2010-06-24 10:09:56.919 TAB RSS[998:207] Element 0 = <NSManagedObject: 0x3b3dcb0> (entity: Tabrss; id: 0x3b06a60 <x-coredata://5B703215-A7D8-4E42-834E-A721D78E84BE/Tabrss/p22> ; data: <fault>)
2010-06-24 10:09:56.920 TAB RSS[998:207] Element 1 = <NSManagedObject: 0x3b3e1c0> (entity: Tabrss; id: 0x3b14720 <x-coredata://5B703215-A7D8-4E42-834E-A721D78E84BE/Tabrss/p23> ; data: <fault>)
2010-06-24 10:09:56.920 TAB RSS[998:207] Element 2 = <NSManagedObject: 0x3b3e370> (entity: Tabrss; id: 0x3b1ebd0 <x-coredata://5B703215-A7D8-4E42-834E-A721D78E84BE/Tabrss/p24> ; data: <fault>)
2010-06-24 10:09:56.921 TAB RSS[998:207] Element 3 = <NSManagedObject: 0x3b3e4e0> (entity: Tabrss; id: 0x3b1ecd0 <x-coredata://5B703215-A7D8-4E42-834E-A721D78E84BE/Tabrss/p25> ; data: <fault>)
2010-06-24 10:09:56.921 TAB RSS[998:207] Element 4 = <NSManagedObject: 0x3b3e660> (entity: Tabrss; id: 0x3b3b3f0 <x-coredata://5B703215-A7D8-4E42-834E-A721D78E84BE/Tabrss/p26> ; data: <fault>)
2010-06-24 10:09:56.922 TAB RSS[998:207] Element 5 = <NSManagedObject: 0x3b3e7d0> (entity: Tabrss; id: 0x3b09d20 <x-coredata://5B703215-A7D8-4E42-834E-A721D78E84BE/Tabrss/p27> ; data: <fault>)
2010-06-24 10:09:56.922 TAB RSS[998:207] Element 6 = <NSManagedObject: 0x3b3e940> (entity: Tabrss; id: 0x3b3cf20 <x-coredata://5B703215-A7D8-4E42-834E-A721D78E84BE/Tabrss/p28> ; data: <fault>)
2010-06-24 10:09:56.924 TAB RSS[998:207] Element 7 = <NSManagedObject: 0x3b3eac0> (entity: Tabrss; id: 0x3b3cf30 <x-coredata://5B703215-A7D8-4E42-834E-A721D78E84BE/Tabrss/p29> ; data: <fault>)
2010-06-24 10:09:56.924 TAB RSS[998:207] Element 8 = <NSManagedObject: 0x3b3ec40> (entity: Tabrss; id: 0x3b3cf40 <x-coredata://5B703215-A7D8-4E42-834E-A721D78E84BE/Tabrss/p30> ; data: <fault>)
2010-06-24 10:09:56.925 TAB RSS[998:207] Element 9 = <NSManagedObject: 0x3b3edb0> (entity: Tabrss; id: 0x3b3cf50 <x-coredata://5B703215-A7D8-4E42-834E-A721D78E84BE/Tabrss/p31> ; data: <fault>)
2010-06-24 10:09:56.925 TAB RSS[998:207] Element 10 = <NSManagedObject: 0x3b3ef20> (entity: Tabrss; id: 0x3b3cf60 <x-coredata://5B703215-A7D8-4E42-834E-A721D78E84BE/Tabrss/p32> ; data: <fault>)
2010-06-24 10:09:56.926 TAB RSS[998:207] Element 11 = <NSManagedObject: 0x3b3f090> (entity: Tabrss; id: 0x3b3cf70 <x-coredata://5B703215-A7D8-4E42-834E-A721D78E84BE/Tabrss/p33> ; data: <fault>)
2010-06-24 10:09:56.926 TAB RSS[998:207] Element 12 = <NSManagedObject: 0x3b3f200> (entity: Tabrss; id: 0x3b3cf80 <x-coredata://5B703215-A7D8-4E42-834E-A721D78E84BE/Tabrss/p34> ; data: <fault>)
2010-06-24 10:09:56.927 TAB RSS[998:207] Element 13 = <NSManagedObject: 0x3b3f380> (entity: Tabrss; id: 0x3b3cf90 <x-coredata://5B703215-A7D8-4E42-834E-A721D78E84BE/Tabrss/p35> ; data: <fault>)
2010-06-24 10:09:56.927 TAB RSS[998:207] Element 14 = <NSManagedObject: 0x3b3f500> (entity: Tabrss; id: 0x3b3cfa0 <x-coredata://5B703215-A7D8-4E42-834E-A721D78E84BE/Tabrss/p36> ; data: <fault>)
(gdb) continue
2010-06-24 10:09:57.932 TAB RSS[998:207] Database read and XML feed created.

What does it mean?:

<NSManagedObject: 0x3b3dcb0> (entity: Tabrss; id: 0x3b06a60 <x-coredata://5B703215-A7D8-4E42-834E-A721D78E84BE/Tabrss/p22> ; data: <fault>

I want to see the contents of a field in a database.

I have 15 records in my database and 12 fields in each record. In my basic understanding, it looks like my array storiescontains the entire record from the database, not individual fields. Maybe I need a 2D array for this, if so, how do I do this?

Ultimately, I want to iterate over an array and create XML tags for each field. But one step at a time ...

Thanks Steven

+5
2

, . :

NSLog (@"Element %i = %@", i, [stories objectAtIndex: i]);

NSLog % @, . , - :

NSLog (@"Element %i contains fields: %d - %s - %d",i,[[stories objectAtIndex: i] getIntegerField],[[stories objectAtIndex: i] getStringField],[[stories objectAtIndex: i] getAnotherIntegerField]);

, , .

+6

, , description NSManagedObject. , . .

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[request setReturnsObjectsAsFaults:NO];

... , , .

, , , valueForKey:@"attributeName".

:

, , .

, Core Data . . . .

Core Data . Core Data - , . , , , , .

NSManagedObject, Tabrss . Tabrss. Tabrss, , Tabrss.

, Tabrss name. Tabrss , :

int i;
for (i = 0; i < arrayItemQuantity; i++)
    NSLog (@"Element %i = %@", i, [[stories objectAtIndex: i] valueForKey:@"name"]);

:

NSManagedObject *aTabrss;
for (aTabrss in stories)
    NSLog(@"aTabrss.name=%@",[aTabrss valueForKey:@"name"]);

NSManagedObject Tabrss, :

TabrssSubclass *aTabrss;
for (aTabrss in stories)
    NSLog(@"ATabrss.name=%@",aTabrss.name]);

, , , , . , .

+14

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