关键阵列CouchDB的搜索和过滤 [英] couchdb search or filtering on key array

问题描述

我有这个在我看来功能：

 发出（[doc.address.country，doc.address.state，doc.address.city] DOC）;
 

当我查询的搜索，我需要填补数组中的所有3个元素，例如：

 ？键= [美国，纽约，纽约]
 

这会产生我的记录，还是让说，例如，我只是想在我们回到一切，例如：

 ？关键=US]
 

或在美国和国...

 ？键= [美国，纽约]
 

或者......可以说，也许是我想从纽约刚刚的所有记录...（我知道下面不工作）

 ？键= [，，NY]
 

我真的不明白如何，如果你想离开阵列的空元素之一搜索？

解决方案

第一：

键=US]将不会在一个数组键[美国，纽约]的工作，因为你正在寻找一个关键是精确[美国。相反，你必须使用

  startkey =US＆放大器; endkey =US，{}]
 

那么这些键是在结果：

  [DE，巴伐利亚，慕尼黑]＆LT; ---- NO！ DE是出于startkey的范围
[美国，FL，迈阿密]＆LT; ----是的，开始以美
[美国，纽约，纽约＆LT; ----是的，开始以美
[VE，XX，Vencuela城＆LT; ---- NO！ VE已经endkey的范围
 

也在努力：

  startkey = [美国，FL＆放大器; endkey = [美国，FL，{}]
 

结果：

  [DE，巴伐利亚，慕尼黑]＆LT; ---- NO！ DE是出于startkey的范围
[美国，FL，迈阿密]＆LT; ----是的，开始以美国，FL
[美国，纽约，纽约＆LT; ---- NO，美国，纽约已经endkey的范围
[VE，XX，Vencuela城＆LT; ---- NO！ VE已经endkey的范围
 

二：
你不能对左侧空白..所以你必须写一些发出：
（您不必发出第二个和第三个数组项，如果你不需要进行查询）

查看byStateCityCountry

 发出（[doc.address.state，doc.address.city，address.country] DOC）;
 

查看byCityStateCountry

 发出（[address.city，doc.address.state，doc.address.country] DOC）;
 

的只是把一个标志摆在首位，以确定查询的类型，所以你可以在一个视图：

 发出（[1，address.country，doc.address.state，doc.address.city] DOC）;
发射（[2，doc.address.state，doc.address.city，address.country] DOC）;
发出（[3，address.city，doc.address.state，doc.address.country] DOC）;
 

用法：

<？pre> startkey = [1，US＆放大器; endkey = [1，美国，{}]
？startkey = [2，FL]放大器; endkey = [2，FL，{}]
？startkey = [3，迈阿密]＆安培; endkey = [3，迈阿密，{}]


I have this in my view function:

emit([doc.address.country,doc.address.state, doc.address.city], doc);

When I query the search, I need to have all 3 elements of the array filled in, for example:

?key=["US","NY","New York"]

that will produce my records, but lets say for example, I just want to return everything in the US for example:

?key=["US"]   

or in the US and State...

?key=["US","NY"] 

OR... lets say perhaps I want just all records from NY... (i know the below doesn't work)

?key=["","NY"]

I don't really get how to search if you want to leave one of the elements of the array empty?

解决方案

First:

key=["US"] will not work on an Array Key ["US","NY"], cause you're looking for a key that is EXACT ["US"]. Instead, you have to use

startkey=["US"]&endkey=["US",{}] 

then those Keys are in the resultset:

["DE","Bavaria","Munich"]   <---- NO ! "DE" is out of Range of startkey
["US","FL","Miami"]         <---- YES, starts with "US"
["US","NY","New York"]      <---- YES, starts with "US"
["VE","XX","Vencuela City"] <---- NO ! "VE" is out of Range of endkey

Also Working:

startkey=["US","FL"]&endkey=["US","FL",{}] 

result:

["DE","Bavaria","Munich"]   <---- NO ! "DE" is out of Range of startkey
["US","FL","Miami"]         <---- YES, starts with "US","FL"
["US","NY","New York"]      <---- NO, "US","NY" is out of Range of endkey
["VE","XX","Vencuela City"] <---- NO ! "VE" is out of Range of endkey

Second: You cannot have blanks on left side.. so you have to write some more emits: ( you do not have to emit the second and third array-item, if you do not need to query it)

view "byStateCityCountry":

emit([doc.address.state, doc.address.city,address.country], doc);

view "byCityStateCountry":

emit([address.city,doc.address.state, doc.address.country], doc);

of just put a flag in the first place to determine the type of query, so you can do all in one View:

emit([1,address.country,doc.address.state, doc.address.city], doc);
emit([2,doc.address.state, doc.address.city,address.country], doc);
emit([3,address.city,doc.address.state, doc.address.country], doc);

Usage:

?startkey=[1,"US"]&endkey=[1,"US",{}]
?startkey=[2,"FL"]&endkey=[2,"FL",{}]
?startkey=[3,"Miami"]&endkey=[3,"Miami",{}]

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