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ArangoDB / AQL更新嵌套文档

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鉴于以下文档结构：

{
  "_key": "abc",
  "_id": "abc",
  "label": "Company ABC",
  "departments": [
    {
      "name": "Department 123",
      "id": "123"
    },
    {
      "name": "Department 456",
      "id": "456"
    }
  ]
}

你能告诉我为什么以下查询不起作用吗？错误消息是"missing document key" . 我在另一个SO（ArangoDB AQL: Update single object in embedded array）中找到了更长时间更复杂的解决方法，但我很好奇这个更简单的查询究竟出了什么问题 .

FOR c IN company
  FOR d in c.deparments
    FILTER d.id == “456”
    UPDATE d WITH { name: “Department 789” } IN company
RETURN d
arangodb aql

1 回答

  • 4

    目前，我只知道如何更新ArangoDB中的顶级属性 . 虽然我希望将来能引起我的注意，但是这里有一些适用于您的场景的选项 .

    使用MERGE更新

    在此示例中，我们通过重写数组并在命中条件时使用 MERGE 函数来更新顶级 departments 属性 .

    LET company = DOCUMENT("companies/abc")

UPDATE company WITH {
  departments:
   (FOR department IN company.departments
     RETURN department.id == "456" ?
       MERGE(department, {name: "Department 789"}) : department)
} IN companies

    使用替代数据模型

    上面的示例假设部门数据嵌入在公司文档中 . 考虑以下：

    "companies" collection

    {
  "_key": "abc",
  "_id": "companies/abc",
  "label": "Company ABC"
}

    "departments" collection (separate docs)

    {
  "_key": "456",
  "_id": "departments/456",
  "company": "companies/abc",
  "name": "Department 456"
}

{
  "_key": "123",
  "_id": "departments/123",
  "company": "companies/abc",
  "name": "Department 123"
}

    Getting Company #ABC with Departments:

    LET company = DOCUMENT("companies/abc")

LET departments =
  (FOR department IN departments
    FILTER department.company == company._id
    RETURN department)

RETURN MERGE(company, {departments})

    结果：

    {
  "_id": "companies/abc",
  "_key": "abc",
  "label": "Company ABC",
  "departments": [
    {
      "_key": "456",
      "_id": "departments/456",
      "company": "companies/abc",
      "name": "Department 456"
    },
    {
      "_key": "123",
      "_id": "departments/123",
      "company": "companies/abc",
      "name": "Department 123"
    }
  ]
}

    Updating Department #456:

    LET department = DOCUMENT("departments/456")

UPDATE department WITH {name: "Department 789"} IN departments

    请注意，您需要在 departments 集合中的 company 属性上添加索引 . 您可以在此处获取有关索引的详细信息：

    https://docs.arangodb.com/3.3/Manual/Indexing/WhichIndex.html

    你必须权衡两种模型的优缺点 .

    回复于

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