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核心数据:从多个实体或关系中获取结果

我有两个实体.Employee实体

@interface Employee : NSManagedObject

@property (nonatomic, retain) NSString * dept;
@property (nonatomic, retain) NSString * email;
@property (nonatomic, retain) NSString * name;
@property (nonatomic, retain) Department *deptEmp;

@end
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Department实体

@interface Department : NSManagedObject

@property (nonatomic, retain) NSString * location;
@property (nonatomic, retain) NSString * name;
@property (nonatomic, retain) Employee *deptEmp1;
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我试图用以下谓词从两者获取信息

NSMutableString *queryString = [NSMutableString stringWithFormat:@"(name = 'Apple') AND (deptEmp1.location like 'Cupertino')"];

NSEntityDescription *entityDescription = [NSEntityDescription entityForName:@"Employee" inManagedObjectContext:self.managedObjectContext];
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并且获取请求是

NSFetchRequest *request = [[NSFetchRequest alloc] init]; …
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iphone cocoa cocoa-touch core-data ios

5
推荐指数
1
解决办法
7321
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