通过ObjectID获取MongoDB集合
[英]Get MongoDB collection by ObjectID
问题描述
MongoDB IDs are unique for a single db cluster. 
MongoDB ID对于单个数据库集群是唯一的。 Is it possible to get the collection a specific ObjectID is used in? 是否有可能在集合中使用特定的ObjectID？
I have the hex representation of an ObjectID and need to know the collection the document with this ID is in. Possible? 我有一个ObjectID的十六进制表示，需要知道具有此ID的文档的集合。可能吗？
2 个解决方案
解决方案1
4 2012-02-01 13:47:28
It's is not a native feature but it is possible by iterating over all collections (db.getCollectionNames()) and invoking a find({_id: <yourid>}) query. 它不是本机功能，但可以通过遍历所有集合(db.getCollectionNames())并调用find({_id: <yourid>})查询来实现。 Obviously this will be a very slow operation so a schema change or using something other than ObjectId as your _id value is probably the way forward for you. 显然，这将是一个非常慢的操作，因此架构更改或使用除ObjectId之外的其他内容作为您的_id值可能是您的前进方向。
解决方案2
2 2012-02-01 11:52:52
I'm not sure about your use case but if you are using ObjectID's for _id the short answer is no. 我不确定你的用例，但如果你使用ObjectID for _id ，简短的回答是否定的。
A BSON ObjectID is a 12-byte value consisting of a 4-byte timestamp (seconds since epoch), a 3-byte machine id, a 2-byte process id, and a 3-byte counter [1]
Or diagrammatically: 或图解：
|0 1 2 3 | 4 5 6 | 7 8 | 9 10 11 |
| time | machine | pid | inc |
So there is no collection information stored there. 因此，那里没有存储任何收集信息。
However, any value can be used for _id so you could use your own convention, which could store collection information if thats required... 但是， 任何值都可以用于_id因此您可以使用自己的约定，如果需要，可以存储集合信息...
[1] http://www.mongodb.org/display/DOCS/Object+IDs#ObjectIDs-TheBSONObjectIdDatatype [1] http://www.mongodb.org/display/DOCS/Object+IDs#ObjectIDs-TheBSONObjectIdDatatype
声明:本站的技术帖子网页，遵循CC BY-SA 4.0协议，如果您需要转载，请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.