Question

在像这样的Azure Documentdb文档中

{
"id": "WakefieldFamily",
"parents": [
    { "familyName": "Wakefield", "givenName": "Robin" },
    { "familyName": "Miller", "givenName": "Ben" }
],
"children": [
    {
        "familyName": "Merriam", 
        "givenName": "Jesse", 
        "gender": "female", 
        "grade": 1,
        "pets": [
            { "givenName": "Goofy" },
            { "givenName": "Shadow" }
        ]
    },
    { 
      "familyName": "Miller", 
      "givenName": "Lisa", 
      "gender": "female", 
      "grade": 8 
    }
],
  "address": { "state": "NY", "county": "Manhattan", "city": "NY" },
  "isRegistered": false
};

如何查询给名字的宠物是“高飞”的孩子？

看起来以下语法无效

Select * from root r
WHERE r.children.pets.givenName="Goofy"

相反，我需要做

Select * from root r
WHERE r.children[0].pets[0].givenName="Goofy"

并没有真正搜索数组。

关于如何处理这类查询的任何建议？

Answer 1

你应该利用DocumentDB的JOIN子句，它在RDBM中的运行方式与JOIN略有不同（因为DocumentDB处理无架构文档的非规范化数据模型）。

简单地说，您可以将DocumentDB的JOIN视为自连接，可用于在嵌套的JSON对象之间形成交叉产品。

在查询名字为“高飞”的儿童的情况下，您可以尝试：

SELECT 
    f.id AS familyName,
    c AS child,
    p.givenName AS petName 
FROM Families f 
JOIN c IN f.children 
JOIN p IN c.pets
WHERE p.givenName = "Goofy"

返回：

[{
    familyName: WakefieldFamily,
    child: {
        familyName: Merriam,
        givenName: Jesse,
        gender: female,
        grade: 1,
        pets: [{
            givenName: Goofy
        }, {
            givenName: Shadow
        }]
    },
    petName: Goofy
}]

参考：http://azure.microsoft.com/en-us/documentation/articles/documentdb-sql-query/

修改

您还可以使用ARRAY_CONTAINS功能，如下所示：

SELECT food.id, food.description, food.tags FROM food WHERE food.id = "09052" or ARRAY_CONTAINS(food.tags.name, "blueberries")

Answer 2

自2014年得到解答以来，我认为ARRAY_CONTAINS函数已经更改。我必须使用以下内容使其起作用。

SELECT * FROM c
WHERE ARRAY_CONTAINS(c.Samples, {TimeBasis:"5MIN_AV", "Value":"5.105"},true)

样本是我的JSON数组，它包含具有许多属性的对象，包括上面的两个。

Azure DocumentDb中数组的WHERE子句

2 个答案: