在NSPredicate中组合“AND”和“OR”条件 [英] Combining 'AND' and 'OR' Condition in NSPredicate

问题描述

再次需要更多帮助来构建我的NSPredicates：（

 类别
 {
 name： string 
 subs<  - >> SubCategory 
} 
 
 SubCategory 
 {
 name：string 
 numbervalue：NSNumber 
} 
  

我想知道如何使用 AND 和 OR 。

例如，我想返回每个具有名称为category_name的类别， valueA OR valueB。

我尝试过各种可能的谓词构造函数组合，

这是我迄今为止最好的尝试。

  NSPredicate * predicate = [NSPredicate predicateWithFormat @（name ==％@）AND（ANY subs.numbervalue ==％@ OR ANY subs.numbervalue ==％@），@aname，value1，value2]; 
   

编辑1

第二次尝试。对'numbervalue'的过滤仍然无效。

  NSNumber valueA = [NSNumber numberWithInt：20]; 
 NSNumber valueA = [NSNumber numberWithInt：90]; 
 NSArray * arr = [NSArray arrayWithObject：valueA，valueB，nil]; 
 
 predicate = [NSPredicate predicateWithFormat：@（name ==％@）AND（ANY subs.numbervalue IN％@），@aname，arr]; 
   
 
 
 
 编辑2  
 
 
 
 1）使用这个结果在整个集合中返回，即使只有一个项目在集合中有值。 
  predicate = [NSPredicate predicateWithFormat：@（ANY subs.numbervalue IN％@），arr]; 
  
 2）使用此结果导致同样的问题，即使只返回1的匹配。
 谓词= [NSPredicate predicateWithFormat：@（（SUBQUERY（subs，$ x，$ x.numbervalue = =％@ or $ x.numbervalue ==％@）。@ count> 0），value1，value2]; 
  
 
 b $ b 
也使用最简单的版本导致相同的问题....我没有注意到这个早。
  NSPredicate * predicate = [NSPredicate predicateWithFormat @（ANY subs.numbervalue ==％@，valueA]; 
  
 
 
  
 
  $ b 
类别与子类别具有一对多关系，并表示为子类别的NSSet。
 
 
 
每个子类别都有一个名为numbervalue的属性。
 
 
 
 编辑3  
 
 
 
要测试我有2个类别
每个都有1到10的数字值; 
 
 
 
使用此代码，每个类别都返回所有10个订阅。
 
 
 
预期结果是返回的两个类别，每个类别只有2个。
 
 
 
我已经找出了所有对象，数据是正确的。问题是我不能返回已过滤的子类别。
  NSFetchRequest * fetchRequest = [[NSFetchRequest alloc] init]; 
 NSManagedObjectContext * context = [[DataSource sharedDataSource] managedObjectContext]; 
 NSEntityDescription * entity = [NSEntityDescription entityForName：@CategoryinManagedObjectContext：context]; 
 [fetchRequest setEntity：entity]; 
 
 [fetchRequest setFetchBatchSize：20]; 
 
 NSSortDescriptor * sortDescriptor = [[NSSortDescriptor alloc] initWithKey：@nameascending：YES]; 
 NSArray * sortDescriptors = [NSArray arrayWithObjects：sortDescriptor，nil]; 
 
 NSPredicate *谓词; 
 NSNumber * a = [NSNumber numberWithFloat：1]; 
 NSNumber * b = [NSNumber numberWithFloat：2]; 
 predicate = [NSPredicate predicateWithFormat：@（SUBQUERY（subs，$ x，$ x.numbervalue ==％@ or $ x.numbervalue ==％@）。@ count> 0），a，b] ; 
 
 [fetchRequest setPredicate：predicate]; 
 [fetchRequest setSortDescriptors：sortDescriptors]; 
 
 NSError * error = nil; 
 [NSFetchedResultsContoller deleteCacheWithName：nil]; 
 
 NSFetchedResultsController * aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest：fetchRequest managedObjectContext：context sectionNameKeyPath：@namecacheName：@Master]; 
 aFetchedResultsController.delegate = self; 
 
 self.fetchedResultsController = aFetchedResultsController; 
 
 if（！[self.fetchedResultsController performFetch：& error]）{
 
 NSLog（@未解析的错误％@，％@，错误，[error userInfo] ）; 
 abort（）; 
} 
  
 
 
解决方案
使用 SUBQUERY 。
  [NSPredicate predicateWithFormat @ ％@）AND（SUBQUERY（subs，$ x，$ x.numbervalue ==％@ or $ x.numbervalue ==％@）。@ count> 0），@aname，value1，value2]; 
  
尝试一下，让我知道。
 
 
 
另一个解决方案可以是抓取整个集合 subs ，然后使用谓词过滤检索的集合，以检查元素是否与 value1 或 value2 。
 
 
 
希望它有帮助。
 
 
 
 编辑 
 
 
 
如果您遵循 Eimantas 建议，请确保创建正确的数组：
  NSNumber valueA = [NSNumber numberWithInt：20]; 
 NSNumber valueB = [NSNumber numberWithInt：90]; 
 NSArray * arr = [NSArray arrayWithObjects：valueA，valueB，nil]; 
  
 
Back again needing more help with constructing my NSPredicates :(
Category
{
   name:string
   subs<-->>SubCategory
}

SubCategory
{
   name:string
   numbervalue:NSNumber
}
I would like to know how to create a predicate with AND and OR.

For example, I would like to return every Category with name == "category_name" that also has a subcategory with a numbervalue of "valueA" OR "valueB".

I've tried every possible combination of predicate constructors I could come up with but I just cant get it to work.

This is my best attempt so far.
NSPredicate *predicate=[NSPredicate predicateWithFormat@"(name== %@) AND (ANY subs.numbervalue==%@ OR ANY subs.numbervalue==%@)", @"aname", value1, value2];
Edit 1

Second attempt. The filtering on the 'numbervalue' is still not working.
NSNumber valueA=[NSNumber numberWithInt:20];
NSNumber valueA=[NSNumber numberWithInt:90];
NSArray *arr=[NSArray arrayWithObject:valueA,valueB,nil];

predicate=[NSPredicate predicateWithFormat:@"(name==%@)AND(ANY subs.numbervalue IN %@)",@"aname",arr];
Edit 2

I've tried filtering just by numberValue and have left the name out alltogether.

1) using this results in the entire set being returned even if only 1 item in the set has the value. 
predicate=[NSPredicate predicateWithFormat:@"(ANY subs.numbervalue IN %@)",arr];
2) Using this results in the same problem, every item in the set being returned even if only 1 of them matches.
predicate=[NSPredicate predicateWithFormat:@"((SUBQUERY(subs, $x, $x.numbervalue == %@ or $x.numbervalue == %@).@count > 0)", value1, value2];
Also using the simplest version results in the same problem.... I didnt notice this earlier.
NSPredicate *predicate=[NSPredicate predicateWithFormat@"(ANY subs.numbervalue==%@ ,valueA];
So I think I have my problem narrowed down. 

Category is an Entity.
SubCategory is an Entity.

Category has a one to many relationship with SubCategory and is represented as an NSSet of SubCategory.

Each SubCategory has an attribute named numbervalue.

Edit 3

To test I have 2 Categorys.
Both Categories have 10 subs, each with a numbervalue of 1 -10;

Using this code both categories are returned along with all 10 subs for each.

Expected result is both categories returned , each with just 2 subs.

I've traced out all my objects and the data is correct. The problem is I cant return a category that has filtered subs.
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
NSManagedObjectContext *context=[[DataSource sharedDataSource]managedObjectContext];
NSEntityDescription *entity = [NSEntityDescription entityForName:@"Category" inManagedObjectContext:context];
[fetchRequest setEntity:entity];

[fetchRequest setFetchBatchSize:20];

NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:YES];
NSArray *sortDescriptors = [NSArray arrayWithObjects:sortDescriptor, nil];

NSPredicate *predicate;
NSNumber *a=[NSNumber numberWithFloat:1];
NSNumber *b=[NSNumber numberWithFloat:2];
predicate=[NSPredicate predicateWithFormat:@"(SUBQUERY(subs,$x,$x.numbervalue==%@ or $x.numbervalue==%@).@count> 0)",a,b];

[fetchRequest setPredicate:predicate];
[fetchRequest setSortDescriptors:sortDescriptors];

NSError *error = nil;
[NSFetchedResultsContoller deleteCacheWithName:nil];

NSFetchedResultsController *aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:context sectionNameKeyPath:@"name" cacheName:@"Master"];
aFetchedResultsController.delegate = self;

self.fetchedResultsController = aFetchedResultsController;

if (![self.fetchedResultsController performFetch:&error]) {

   NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
   abort();
}

解决方案
I'll do the following using a SUBQUERY.
[NSPredicate predicateWithFormat@"(name == %@) AND (SUBQUERY(subs, $x, $x.numbervalue == %@ or $x.numbervalue == %@).@count > 0)", @"aname", value1, value2];
Try it and let me know.

Another solution could be to grab the whole collection subs and then filter the retrieved set with a predicate to check if elements match for value1 or value2.

Hope it helps.

Edit

If you follow Eimantas suggestion make to sure to create the right array:
NSNumber valueA = [NSNumber numberWithInt:20];
NSNumber valueB = [NSNumber numberWithInt:90];
NSArray *arr = [NSArray arrayWithObjects:valueA, valueB, nil];


                        
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