Re: Silly, can I use @max to get the object with the latest date?
Re: Silly, can I use @max to get the object with the latest date?
- Subject: Re: Silly, can I use @max to get the object with the latest date?
- From: Gustavo Pizano <email@hidden>
- Date: Sun, 15 May 2011 12:46:38 +0200
Hello Evadne
I tried this one out it worked...
Will try yours also
NSInteger vNumber = 1;
NSSet * versions = [self valueForKey:@"toVersions"];
if(!versions || [versions count] == 0)
return vNumber;
else{
NSDate * d = [versions valueForKeyPath:@"@max.creationDate"];
DPAVersion * latest = [[[versions filteredSetUsingPredicate:[NSPredicate predicateWithFormat:@"creationDate==%@",d]] allObjects] lastObject] ;
vNumber = [[latest valueForKey:VERSION_NUMBER_KEY] integerValue];
vNumber ++;
}
return vNumber;
On May 15, 2011, at 12:40 PM, Evadne Wu wrote:
> Hi Gustavo,
>
> How about setting the sort descriptor’s ascending to NO, and limit the number of fetched objects to one? Something like this…?
>
> [request setSortDescriptors:[NSArray arrayWithObject:[NSSortDescriptor sortDescriptorWithKey:@"date" ascending:NO]]]; // descending = arranged from largest (latest)
> [request setFetchLimit:1];
>
> -ev
>
> On May 15, 2011, at 18:02, Gustavo Pizano wrote:
>
>> Hello all.
>>
>> I have a Entity A that has a to-many relationship. to B
>>
>> Now I need to get the latest B of A.
>>
>> I was reading NSFetchRequest, and NSPredicate, for NSPredictate I could use something like
>>
>> predicate = [NSPredicate predicateWithFormat:@"birthday > %@", referenceDate];
>> filteredArray = [array filteredArrayUsingPredicate:predicate];
>>
>> but the operator is a comparison, I wish to know if its possible to fetch the object with he latest date without having to looping through the objects manually and comparing the dates.
>>
>> And NSFetchRequest will fetch me on the whole table of B.
>>
>>
>> I know its silly question but I hadn't found the way..
>>
>> thanks
>>
>>
>> Gustavo
>>
>> _______________________________________________
>>
>> Cocoa-dev mailing list (email@hidden)
>>
>> Please do not post admin requests or moderator comments to the list.
>> Contact the moderators at cocoa-dev-admins(at)lists.apple.com
>>
>> Help/Unsubscribe/Update your Subscription:
>>
>> This email sent to email@hidden
>
_______________________________________________
Cocoa-dev mailing list (email@hidden)
Please do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden