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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和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]; …Run Code Online (Sandbox Code Playgroud)