我有一个名单,有3200名字典。 每个字典有20个关键/价值。 如何以最佳方式通过它进行搜索?
我有一句叫“id”的一句大话,现在我做的是,通过阵列的所有内容,要求每个要素(字典)对钥匙“id”的价值进行对比,如果发现的话,则与其他id相比。
This is really slow, like I can see a lag of about 1-2 seconds. Is there a better way? Thanks
我有一个名单,有3200名字典。 每个字典有20个关键/价值。 如何以最佳方式通过它进行搜索?
我有一句叫“id”的一句大话,现在我做的是,通过阵列的所有内容,要求每个要素(字典)对钥匙“id”的价值进行对比,如果发现的话,则与其他id相比。
This is really slow, like I can see a lag of about 1-2 seconds. Is there a better way? Thanks
What you re doing now is an O(n) operation (linear in the number of items in the list). You can get a "constant time" O(1) lookup if you keep another "lookaside" data structure that helps you index into your list.
在你撰写3 200个字典清单之前,又创建了一个特别字典,标明你的身份证,以便把大阵列索引。 换言之,每个钥匙都将是身份证,其价值将是一个具有指数编号的NSNumber。 之后(在同一名单中或单独一个名单中)也除外。
然后,当你需要做一项研究时,就在座标语中只读到<>-objectForKey:,这将会立即使你回到你看望的条目索引上。
如果你用活的数据更新,那么你总是把眼部的字典归到一起。 请注意,这也假设了你的身份证是独一无二的(如其正确无误)。
为什么你不使用Skkite数据库?
我注意到的第一件事是,你似乎总是在同一个<代码>id钥匙上搜索。 如果是这样的话,那么你就应当按照<条码>d条码>对你的各种字典进行分类。 然后,你可以就分类阵列进行双轨搜索。 结果:通过<条码>查询任何字典> 最多为12项行动。 相比之下,通过3 200件物品进行的线性搜索平均为1 600件,可能需要多达3 200件。
如果你需要寻找几个不同的钥匙,如果所有独裁者都拥有同样的钥匙,那么核心数据可能是一个非常好的解决方案。 NSManaged 标 题 理论家,但框架将照顾到你们的指数化,搜寻工作迅速而比较容易。
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