coredata keypath nameOfMovie在实体中找不到< NSSQLEntity Theaters id = 3> [英] coredata keypath nameOfMovie not found in entity <NSSQLEntity Theaters id=3>

问题描述

我有一个coredata项目，我试图进行查询。这是我的coredata模型：

I have a coredata project and I'm trying to make a query. Here is my coredata model:

NSManagedObjectContext *moc = [self managedObjectContext];
    NSEntityDescription *theaterDescription = [ NSEntityDescription entityForName:@"Theaters" inManagedObjectContext:moc];

     NSPredicate *theaterPredicate = [NSPredicate predicateWithFormat:@"nameOfTheater like %@ AND nameOfMovie like %@",_theaterName,_movieOutlet.stringValue];


    NSFetchRequest *theaterRequestTwo = [NSFetchRequest new];
    theaterRequestTwo.entity = theaterDescription;
    theaterRequestTwo.predicate = theaterPredicate;



    NSError *error = nil;

    NSArray *theaterResults = [moc executeFetchRequest:theaterRequestTwo error:&error];

但我收到此错误：

keypath nameOfMovie not found in entity <NSSQLEntity Theaters id=3>

我也尝试过：

NSPredicate *theaterPredicate = [NSPredicate predicateWithFormat:@"nameOfTheater like %@ AND Movies.nameOfMovie like %@",_theaterName,_movieOutlet.stringValue];

但我遇到了这个错误：

keypath Movies.nameOfMovie not found in entity <NSSQLEntity Theaters id=3>

我也尝试过：

NSPredicate *theaterPredicate = [NSPredicate predicateWithFormat:@"nameOfTheater like %@ AND movies.nameOfMovie like %@",_theaterName,_movieOutlet.stringValue];

我收到以下错误：

to-many key not allowed here

to-many key not allowed here

任何人都知道我做错了什么或我的代码缺少什么。非常感谢您的帮助。

By any chance any of you knows what I'm doing wrong or what I'm missing on my code. I'll really appreciate your help.

更新：

我的coredata模型的标头文件：

This are the headers files for my coredata model:

theaters classe：

theaters classe:

@class Movies;

@interface Theaters : NSManagedObject

@property (nonatomic, retain) NSString * nameOfTheater;
@property (nonatomic, retain) NSSet *movies;
@end

@interface Theaters (CoreDataGeneratedAccessors)

- (void)addMoviesObject:(Movies *)value;
- (void)removeMoviesObject:(Movies *)value;
- (void)addMovies:(NSSet *)values;
- (void)removeMovies:(NSSet *)values;

---

电影类：

---

Movies class:

@class Schedules, Theaters;

@interface Movies : NSManagedObject

@property (nonatomic, retain) NSString * nameOfMovie;
@property (nonatomic, retain) NSSet *showTimes;
@property (nonatomic, retain) Theaters *theaters;
@end

@interface Movies (CoreDataGeneratedAccessors)

- (void)addShowTimesObject:(Schedules *)value;
- (void)removeShowTimesObject:(Schedules *)value;
- (void)addShowTimes:(NSSet *)values;
- (void)removeShowTimes:(NSSet *)values;

---

计划类别：

---

Schedules class:

@interface Schedules : NSManagedObject

@property (nonatomic, retain) NSDate * showTimes;
@property (nonatomic, retain) NSSet *movie;
@end

@interface Schedules (CoreDataGeneratedAccessors)

- (void)addMovieObject:(Movies *)value;
- (void)removeMovieObject:(Movies *)value;
- (void)addMovie:(NSSet *)values;
- (void)removeMovie:(NSSet *)values;

推荐答案

可以使用 SUBQUERY 这种问题

一个确切的剧院实体（由您的示例复制）

one exact theater entity (copied by your example)

NSPredicate *predicate = [NSPredicate predicateWithFormat:@"nameOfTheater like %@ AND SUBQUERY(movies, $mv, $mv.nameOfMovie like %@).@count > 0", _theaterName,_movieOutlet.stringValue];

UPDATE

所有影院运行电影abc

all theaters where movie abc is running

NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SUBQUERY(movies, $mv, $mv.nameOfMovie CONTAINS[c] %@).@count > 0", @"abc"];

btw，您的模型是否正确？

btw, is you model correct?

Theaters <->> Movies = 1:n

有电影，但电影只在一​​个剧院
因此，如果您以名称abc获取 Movie ，您可以获得 Theater 。或者

So every Theater has x Movies, but a Movie is running in only one Theater So if you fetch a Movie with name "abc" you can get the Theater as attibute. Or is it

Theaters <<->> Movies = n:m

？因此电影和 movieTheaters 是 NSSet< Movie> / NSSet< Theater>

UPDATE 2

仍然需要回答上述问题。什么是正确的关系？是一个电影在x影院或只在一个。你的头文件是如何为ManagedObject类？ ;）

still need an answer for the question above. what is the correct relation between? is one movie in x theaters or only in one. how are your header files for the ManagedObject classes? ;)

NSEntityDescription *schedulesDescription = [NSEntityDescription entityForName:@"Schedules" inManagedObjectContext:moc];

// something like this if 1:n. Try and post logs, have no IDE at the moment
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"movie.nameOfMovie == %@ AND movie.movieTheaters.nameOfTheater == %@", @"movie8", @"theaterOne"];

// if n:m, as far as I remember you couldn't fetch over 2 n:m relations via .
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"movie.nameOfMovie == %@ AND SUBQUERY(movie, $mv, $mv.movieTheaters.nameOfTheater == %@).@count > 0", @"movie8", @"theaterOne"];

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