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POcoredata filtering by date using NSPredicate returns nothing
 

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  1. POcoredata filtering by date using NSPredicate returns nothing
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    <p>Hi i am new to this coredata. I have two entities CategoryList and ExpenseList. CategoryList consists of two attributes<br> 1.dates (nsdate)<br> 2.categories (nsstring)<br> and in to many relation with ExpenseList, relationship name is "expenseList" ExpenseList consists of 1.amountSpent (float).<br> I just wanted to know learn about relationship features in coredata. When i tried to create a nspredicate to filter the data by a specific date, its returning nothing. I just wanted to filter the categories attribute content in the CategoryList entity for a specific date. Here is my code</p> <pre><code>-(void) callingByDate { NSManagedObjectContext *managedObjectContext = [self managedObjectContext]; NSEntityDescription *categoryL = [NSEntityDescription entityForName:@"CategoryList" inManagedObjectContext:managedObjectContext]; NSSortDescriptor *dateSort = [[NSSortDescriptor alloc]initWithKey:@"date" ascending:YES]; NSArray *sortDescriptors = [[NSArray alloc]initWithObjects:dateSort, nil]; NSPredicate *predicate = [NSPredicate predicateWithFormat:@"dates == %@",date]; NSFetchRequest *dateFetch = [[NSFetchRequest alloc]init]; [dateFetch setSortDescriptors:sortDescriptors]; [dateFetch setEntity:categoryL]; [dateFetch setPredicate:predicate]; NSMutableArray *results = [[managedObjectContext executeFetchRequest:dateFetch error:nil] mutableCopy]; if([results count] &gt; 0) NSLog(@"results found"); else NSLog(@"no results found"); } </code></pre> <p>when i execute this code in the nslog area its showing 'no results found'. I could not figure out why . Thanks in advance</p> <p>here is my code to find the end and start of the day</p> <pre><code>-(NSDate *)beginningOfDay:(NSDate *)date; { NSDate *dat = [NSDate date]; NSCalendar *cal = [NSCalendar currentCalendar]; NSDateComponents *components = [cal components:( NSMonthCalendarUnit | NSYearCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit ) fromDate:dat]; [components setHour:0]; [components setMinute:0]; [components setSecond:0]; return [cal dateFromComponents:components]; } -(NSDate *)endOfDay:(NSDate *)date; { NSDate *dat = [NSDate date]; NSCalendar *cal = [NSCalendar currentCalendar]; NSDateComponents *components = [cal components:( NSMonthCalendarUnit | NSYearCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit ) fromDate:dat]; [components setHour:23]; [components setMinute:59]; [components setSecond:59]; return [cal dateFromComponents:components]; </code></pre> <p>when i nslog, the result showing is startday -2013-04-30 18:30:00 +0000 endOfDay -2013-05-01 18:29:59 +0000</p>
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    1. PO
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    1. This table or related slice is empty.
    1. PTQuestion
    1. USArun Kumar
    1. USArun Kumar
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
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      1. POcoredata filtering by date using NSPredicate returns nothing
      1. This table or related slice is empty.
      1. VTUpMod
    1. CO@ user523234 i will give it a try. Could you find any other mistakes rather than this. thanks for the reply
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      1. POcoredata filtering by date using NSPredicate returns nothing
      1. USArun Kumar
    2. COYou never actually declare what date is.
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      1. POcoredata filtering by date using NSPredicate returns nothing
      1. USsosborn
    3. CO@sosborn yes i did. i declared that in the viewDidLoad. the 'date' string will give the current device date.
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      1. POcoredata filtering by date using NSPredicate returns nothing
      1. USArun Kumar
 

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