密码中的嵌套has_many关系

问题描述

我有一个嵌套的has_many关系，试图映射到json结果.

I have a nested has_many relationship that I'm trying to map to a json result.

博客中的以下示例显示了我想做的事情，除了它不是嵌套的

The following example from the blog shows the kind of thing I want to do, except it's not nested

 MATCH (a:Person { name: "Andres" })-[:FATHER_OF]->(child)
  RETURN
  {name:a.name, kids:collect(child.name)} as document

我想要的是这样的

 MATCH (a:Person { name: "Andres" })-[:FATHER_OF]->(child)-[:has_read]->(book)-[:has_chapter]->(chapter)
  RETURN
  {name:a.name, kids:collect({"name":child.name, has_read:collect(book)})} as document

在这种情况下，我想返回一个结构如下的json对象:

In this case I would like to return a json object of a structure like this:

{
  "name": "Andres"
  "kids": [
           {
             "name":"Bob"
             "has_read": [
                           {
                            "name":"Lord of the Rings",
                            "chapters": ["chapter1","chapter2","chapter3"]
                           },
                           {
                            "name":"The Hobbit",
                            "chapters": ["An unexpected party","Roast mutton"]
                           }
                         ]
           },
           {
             "name":"George"
             "has_read": [
                           {
                            "name":"Lord of the Rings",
                            "chapters": ["chapter1","chapter2","chapter3"]
                           },
                           {
                            "name":"Silmarillion",
                            "chapters": ["chapter1","chapter2"]
                           }
                         ]
           }

          ]
}

推荐答案

可以尝试:

如果您与该章保持一致，则需要与众不同collect(distinct book.title)否则.

if you keep the match to the chapter you will need distinctcollect(distinct book.title) otherwise not.

MATCH (a:Person { name: "Andres" })-[:FATHER_OF]->(child),
      (child)-[:has_read]->(book)-[:has_chapter]->(chapter)
WITH a,child,collect(distinct book.title) as books
RETURN
  {name:a.name,
   kids:collect({name:child.name,
                 has_read:books})} as document

哦，如果您也想在结果中包括这些章节，则只需添加一个带有:)

Oh and if you want to include the chapters in the results too, then just add another with :)

MATCH (a:Person { name: "Andres" })-[:FATHER_OF]->(child),
      (child)-[:has_read]->(book)-[:has_chapter]->(chapter)
WITH a,child, {title: book.title, chapters: collect(chapter.title)} as book_doc
WITH a,child, collect(book_doc) as books
RETURN
  {name:a.name,
   kids:collect({name:child.name,
                 has_read:books})} as document

请参阅: http://console.neo4j.org/r/kua2pi

这篇关于密码中的嵌套has_many关系的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！