如何使用ArangoDB中的自连接访问集合中多个文档中的数据

我已将数据以集合名DSP的形式存储在ArangoDB 2.7.1中：

{"content": "Book.xml", "type": "string", "name": "name", "key": 102}
{"content": "D:/XMLexample/Book.xml", "type": "string", "name": "location", "key": 102}
{"content": "xml", "type": "string", "name": "mime-type", "key": 102}
{"content": 4130, "type": "string", "name": "size", "key": 102}
{"content": "Sun Aug 25 07:53:32 2013", "type": "string", "name": "created_date", "key": 102}
{"content": "Wed Jan 23 09:14:07 2013", "type": "string", "name": "modified_date", "key": 102}
{"content": "catalog", "type": "tag", "name": "root", "key": 102}
{"content": "book", "type": "string", "name": "tag", "key": 103} 
{"content": "bk101", "type": {"py/type": "__builtin__.str"}, "name": "id", "key": 103}
{"content": "Gambardella, Matthew", "type": {"py/type": "__builtin__.str"}, "name": "author", "key": 1031} 
{"content": "XML Developer's Guide", "type": {"py/type": "__builtin__.str"}, "name": "title", "key": 1031}
{"content": "Computer", "type": {"py/type": "__builtin__.str"}, "name": "genre", "key": 1031}
{"content": "44.95", "type": {"py/type": "__builtin__.str"}, "name": "price", "key": 1031}
{"content": "2000-10-01", "type": {"py/type": "__builtin__.str"}, "name": "publish_date", "key": 1031}
{"content": "An in-depth look at creating applications with XML.", "type": {"py/type": "__builtin__.str"}, "name": "description", "key": 1031}

这里，单个集合

{“content”：“Book.xml”，“type”：“string”，“name”：“name”，“key”：102}

表示集合中的单个文档

现在，我想访问多个文档中具有类似

key

属性值的所有文档，或者对于相同的

key

值，在类型为computer的情况下，访问具有类似值title和price的所有文档。我已经在DSP filter p p中尝试了一个AQL作为

用于p。name==“publish_date”和p.content==“2000-10-01和p.name=='title'返回p

，但这返回的是一个空集，因为它在单个文档中进行比较，而不是在集合中进行比较

像关系数据库一样，需要某种类型的自连接，但我不知道如何应用自连接。请告诉我如何访问键属性值相同的所有文档，其中

publish\u date

为“2000-10-01”。我希望此查询的结果出现在以下文档中，因为对应于值为2000-10-01的

publish\u date

，

key

的值为1031：

{"content": "Gambardella, Matthew", "type": {"py/type": "__builtin__.str"}, "name": "author", "key": 1031} 
{"content": "XML Developer's Guide", "type": {"py/type": "__builtin__.str"}, "name": "title", "key": 1031}
{"content": "Computer", "type": {"py/type": "__builtin__.str"}, "name": "genre", "key": 1031}
{"content": "44.95", "type": {"py/type": "__builtin__.str"}, "name": "price", "key": 1031}
{"content": "2000-10-01", "type": {"py/type": "__builtin__.str"}, "name": "publish_date", "key": 1031}
{"content": "An in-depth look at creating applications with XML.", "type": {"py/type": "__builtin__.str"}, "name": "description", "key": 1031}

---

假设发布日期存储在属性

name

中，其值存储在属性

content

中，则首先需要查找具有该组合的所有文档：

FOR self IN DSP 
  FILTER self.name == 'publish_date' && self.content == '2000-10-01'
  RETURN self

现在，找到这些文档后，您可以再次将它们加入DSP集合，筛选出具有相同

键

值的文档，但从的初始

中排除已找到的文档：

FOR self IN DSP 
  FILTER self.name == 'publish_date' && self.content == '2000-10-01'
  FOR other IN DSP 
    FILTER other.key == self.key && other._key != self._key 
    RETURN { self, other }

如果您总是根据名称、内容和/或键进行筛选，那么为这些属性编制索引可能是明智的。看起来
键
本身就应该有一个索引。散列索引应该足够了，因为
键
总是相等的<代码>名称

和内容（按此顺序）可以放入skiplist索引中