显式设置 CouchDB 文档键
CouchDB 文档似乎附有一个密钥；它在检索单个文档时不会显示，但您可以使用它们来检索文档范围，例如：
wget "http://localhost:5984/monitor20n/_all_docs?startkey=1111&endkey=2222
但是，显然该键始终与文档 ID 相同，因此您获得的只是这样的东西
{"total_rows":14269,"offset":0,"rows":[
{"id":"128127896626798592","key":"128127896626798592","value":{"rev":"1-4e07e2c4b4eddfad5846ddf905337197"}},
{"id":"128128575021907970","key":"128128575021907970","value":{"rev":"1-43d983af1e837a4415b6167cae3b5de8"}},
... and so on }}
（请参阅此处键== ID ）。但是，您可以在视图中使用更复杂的键，包括允许更复杂交互的向量；至少，您可以设置视图的键，这样您现在就可以提前搜索内容，而无需查找文档 ID。 现在的问题是：您可以在创建文档时设置这些键吗？或者也许在创建之后？ 一个明显的解决方法是创建一个这样的视图
function (doc) {
emit(doc.key,doc)
}
，但是，我想知道是否有更直接的方法来获得相同的效果。
CouchDB docs seem to have a key attached; it does not show up when retrieving a single document but you can use them to retrieve ranges of documents such as :
wget "http://localhost:5984/monitor20n/_all_docs?startkey=1111&endkey=2222
However, apparently that key is always the same as the document id, so that all you obtain is stuff like this
{"total_rows":14269,"offset":0,"rows":[
{"id":"128127896626798592","key":"128127896626798592","value":{"rev":"1-4e07e2c4b4eddfad5846ddf905337197"}},
{"id":"128128575021907970","key":"128128575021907970","value":{"rev":"1-43d983af1e837a4415b6167cae3b5de8"}},
... and so on }}
(see here key == id ). However, you can use more complex keys in views, including vectors which allow for much more complex interaction; at least, you can set the keys of views so you can now in advance what to search without looking up document ids.
The question is now: Can you set those keys up when creating a document? Or maybe after creating it?
An obvious workaround is to create a view like this
function (doc) {
emit(doc.key,doc)
}
however, I would like to know if there's a more direct way of obtaining the same effect.
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键是 CouchDB 视图的重要组成部分。对于视图，键不必是文档 ID。但生成键的唯一方法是在视图中使用 emit 函数。您可以设置的任何属性都不会自动成为键。
将 _all_docs 视为内置视图。为了保持一致，它遵循与常规视图相同的输出，并使用 id 作为键。但您无法更改 _all_docs 视图。如果您想在保存文档时提供自己的_id，那么这将成为关键。
因此，如果您想在“_all_docs”视图中自定义“键”，您可以创建如下文档：
{ _id: 'Sample1' }, {_id: 'My2'}。保存它们后，当您请求“_all_docs”视图时，您将得到：
{“总行数”：2，“偏移量”：0，“行数”：[
{“id”：“样本1”，“键”：“样本1”，“值”：{“rev”：“1-4e07e2c4b4eddfad5846ddf905337197”}}，
{"id":"My2","key":"My2","value":{"rev":"1-43d983af1e837a4415b6167cae3b5de8"}},
...等等 }}
这里有一个关于 documentID 的构成的链接：
http://wiki .apache.org/couchdb/HTTP_Document_API#Special_Fields
虽然没有明确说明，但您不能使用对象或数组作为 DocumentID。
希望有帮助。
Keys are an important part of CouchDB views. With a view, the key does not have to be the document ID. But the only way to produce a key is to use the emit function from within a view. There is no property that you can set that will automatically become the key.
Think of _all_docs like a built in view. To be consistent it follows the same output as a regular view, and it uses the id as the key. But you can't change the _all_docs view. If you wanted to provide your own _id when you save a document, that will end up being the key.
So if you wanted custom 'keys' in the '_all_docs' view you could create docs like this:
{ _id: 'Sample1' }, {_id: 'My2'}. and after they are saved, when you request the '_all_docs' view you would get:
{"total_rows":2,"offset":0,"rows":[
{"id":"Sample1","key":"Sample1","value":{"rev":"1-4e07e2c4b4eddfad5846ddf905337197"}},
{"id":"My2","key":"My2","value":{"rev":"1-43d983af1e837a4415b6167cae3b5de8"}},
... and so on }}
Here is a link about what makes a documentID:
http://wiki.apache.org/couchdb/HTTP_Document_API#Special_Fields
While it does not say explicitly, you can't use objects or arrays as DocumentIDs.
Hope that helps.