DocumentDB-集合内的WHERE子句 [英] DocumentDB - WHERE clause within collection

问题描述

从Microsoft的示例中获得一个像这样的示例文档:

Given a sample document like this one from the Microsoft examples:

{
  "id": "AndersenFamily",
  "lastName": "Andersen",
  "parents": [
     { "firstName": "Thomas" },
     { "firstName": "Mary Kay"}
  ],
  "children": [
     {
         "firstName": "Henriette Thaulow", 
         "gender": "female", 
         "grade": 5,
         "pets": [{ "givenName": "Fluffy" }]
     }
  ],
  "address": { "state": "WA", "county": "King", "city": "seattle" },
  "creationDate": 1431620472,
  "isRegistered": true
}

我们可以看到有一个包含文档数组的子集合children.

We can see that there is a sub-collection children containing an array of documents.

假设我想使用SELECT ... FROM ... WHERE ...类型的语法编写查询，那么我将如何编写查询来查找有任何女儿(有女"性别的孩子)的家庭?

Let's say I wanted to write a query using the SELECT ... FROM ... WHERE ... type syntax, how would I go about writing a query to find families with any daughters (any children with gender "female")

类似

SELECT c.id
FROM c
WHERE c.children.contains(  // I'm stuck!

我想知道我是否想念JOIN之类的东西，但是老实说我不确定从这里走到哪里，而且我在努力寻找某些对Google有用的东西，因为我不确定如何用词组我的搜索！

I'm wondering if I'm missing a JOIN or something but honestly I'm not sure where I go from here, and I'm struggling to find anything helpful in Google partially because I'm not sure how to phrase my search!

推荐答案

您需要JOIN关键字来展开子级，然后将过滤器应用于性别，如以下查询所示:

You need the JOIN keyword to unwind the children, then apply the filter on gender like the query below:

SELECT f.id
FROM family f
JOIN child IN f.children
WHERE child.gender = "female"

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