在 Fauna 数据库中过滤文档的嵌套树？

Question

我在 Fauna 中有以下单个文档的数据结构：

"data": {
 "title": "Title1",
 "blocks": [
  { 
    "block_1": {
     "text": "Text1",
     "refs": Ref(Collection("xyz"), "XYZ") 
  },
  { 
    "block_2": {
     "text": "Text2",
     "refs": Ref(Collection("xyz"), "XYZ2") 
  }
 ]
}

说给文件。 FQL 中是否有一种方法可以根据“refs”值获取“块”？例如。只有 return “block_1” 基于 “refs” = XYZ。 IE。上面的例子应该只 return “block_1”.

我希望问题很清楚。随时要求澄清。 :slight_smile:

感谢您的帮助。

Answer 1

Let({
  blocks: Select(["data", "blocks"], Get(Ref(Collection("Blocks"), "299664869783765505"))),
  entitiesArray: Map(Var("blocks"), block => ToArray(block)),
  entities: Reduce((acc,value) => Append(acc, value) ,[],Var("entitiesArray")),
  find: Filter(Var("entities"), entity => Equals(Select([1, "refs"], entity), Ref(Collection("xyz"), "1")))
}, 
ToObject(Var("find"))
)

但我建议修改 blocks 结构。尝试将其保存为数组

"blocks": [
  {"text": "Text1", "refs": Ref(Collection("xyz"), 1) }, 
  {"text": "Text2", "refs": Ref(Collection("xyz"), 2) }
]

所以 FQL 会是

Let({
  blocks: Select(["data", "blocks"], Get(Ref(Collection("Blocks"), "299664869783765505"))),
  find: Filter(Var("blocks"), entity => Equals(Select(["refs"], entity), Ref(Collection("xyz"), "1")))
}, 
Var("find")
)

或对象

"blocks": {
  "block_1": {
    "text": "Text1",
    "refs": Ref(Collection("xyz"), 1) 
   },
   "block_2": {
     "text": "Text2",
     "refs": Ref(Collection("xyz"), 2) 
   }
}

FQL

Let({
  blocks: Select(["data", "blocks"], Get(Ref(Collection("Blocks"), "299664869783765505"))),
  entities: ToArray(Var("blocks")),
  find: Filter(Var("entities"), entity => Equals(Select([1,"refs"], entity), Ref(Collection("xyz"), "1")))
}, 
ToObject(Var("find"))
)

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