核心数据无效规则不起作用？ [英] Core Data Nullify rule doesn't work?

问题描述

我有一个关系 Order&-;> Row ，两个关系删除规则都设置为 Nullify 。但是，当我如下删除行时，不会将其从订单的行列表中删除吗？

I have a relationship Order<-->>Row with both relationship delete rules set to Nullify. But when I delete a row as below, it is not removed from the Order's row-list?

// Prints "1" as there is one row in the order
NSLog(@"Number of children before: %d", order.rows.count);

for (Row *row in order.rows)
    [moc deleteObject:row];

// Prints "1", should be "0"
NSLog(@"Number of children after: %d", order.rows.count);

这可以强制执行该行为，但这不是必需的。可能是什么问题？

This can force the behavior, but it shouldn't be needed. What might be wrong?

for (Row *row in order.rows)
{
    [moc deleteObject:row];
    [order removeRowsObject:row];
}

推荐答案

那不是nullify所做的。请改用级联。我在两天前回答了类似的问题，如果需要更多详细信息，请查看它：删除（更新）cor​​eData对象

That's not what nullify does. Use cascade instead. I answered a similar question to this 2 days ago, look at it if you need more detail: Deleting (updating) coreData objects

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