这很有趣.在我的应用程序中,我在数据库中创建了数千个条目(在另一个线程中,我正在使用MagicalRecord).一切似乎都很好(从背景/前景/上下文的角度来看).
当在主线程中,我尝试获取"刚插入"的数据时,我发现了以下行为:
- (NSArray *) familiesInCompany:(Company *) company {
NSPredicate *predicate1 = [NSPredicate predicateWithFormat:@"company == %@", company];
NSPredicate *predicate2 = [NSPredicate predicateWithFormat:@"company.name == %@", company.name];
NSArray *first = [Family MR_findAllSortedBy:@"name" ascending:YES withPredicate:predicate1];
NSArray *second = [Family MR_findAllSortedBy:@"name" ascending:YES withPredicate:predicate2];
NSArray *third = [Family MR_findByAttribute:@"company" withValue:company andOrderBy:@"name" ascending:YES];
return second;
}
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现在我得到的是:
Family对象,如预期的那样通过调试SQL语句,我得到以下内容:
"第一"声明:
CoreData:注释:总获取执行时间:0行为0.0000s.
"第二个"声明":
CoreData:sql:SELECT 0,t0.Z_PK,t0.Z_OPT,t0.ZNAME,t0.ZCOMPANY FROM ZFAMILY t0 JOIN ZCOMPANY t1 ON t0.ZCOMPANY = t1.Z_PK WHERE t1.ZNAME =?ORDER BY t0.ZNAME
CoreData:annotation:sql连接获取时间:0.0005s
CoreData:注释:总获取执行时间:2行0.0007秒.
"第三"声明: …