Mongodb 递归查询与 $graphLookup 不按预期工作 [英] Mongodb recursive query not working as expected with $graphLookup
问题描述
在我的文档中,我有 _id、公司名称和赞助商(通过 _id 标识父文档).
例如,我有第一条没有赞助商(父母)的记录
_id:607536219910ef23e80e0bbe公司名称:主要公司"赞助商:"
然后是公司 1,主要公司是母公司:
_id:607e16760a9d2c16e06bc252公司名称:公司 1"赞助商:607536219910ef23e80e0bbe"
还有公司 2,其中公司 1 是母公司:
_id:607e187b0a9d2c16e06bc253公司名称:公司 2"赞助商:607e16760a9d2c16e06bc252"
还有公司 3,其中公司 2 是母公司:
_id:607e1f470a9d2c16e06bc254公司名称:公司 3"赞助商:607e187b0a9d2c16e06bc253"
我正在做一个 $match 来为主要公司带来孩子们的记录
<代码>{赞助商:'607536219910ef23e80e0bbe'}
然后我 $addFields userid,这是一个 _Id 转换为字符串.这是稍后与赞助商匹配:
{"userid": { "$toString": "$_id";}}
现在,当我使用 graphLookup 时,我得到 Main Company 的子公司(公司 2),但我没有将公司 3 作为公司 2 的子公司.我只得到公司 1 和公司 2:
这是我的graphLookup
<代码>{来自:'请',startWith: "$userid",connectFromField: 'userid',connectToField: '赞助商',如:'下线',最大深度:100,限制搜索匹配:{}}
任何帮助将不胜感激.
更新:
正如 Turivishal 在下面所说,查询有效,但这些是我期望的结果:
<代码>[{_id":607536219910ef23e80e0bbe",公司名称":主要公司",下线":[{_id":607e16760a9d2c16e06bc252",公司名称":公司 1",赞助商":607536219910ef23e80e0bbe",下线":[{_id":607e187b0a9d2c16e06bc253",公司名称":公司 2",赞助商":607e16760a9d2c16e06bc252",下线":[{_id":607e1f470a9d2c16e06bc254",公司名称":公司 3",赞助商":607e187b0a9d2c16e06bc253"}]}]}],赞助商":",用户 ID":607536219910ef23e80e0bbe"}
TURIVISHAL 的解决方案:
根据 Turivishal 解决方案,这是最终的流水线,它提供了重复查询的完美下线/层次结构/树视图,并与 Angular Treeview 控件完美配合.非常感谢 Turivishal.我相信你应该发布一个答案,这样我才能接受它,它可以对其他人有用.
他的解决方案与他提出的解决方案非常相似,但要好得多.我最终创建了一个名为 PLID 的新字段,它复制了 _id 字段,并且效果非常好.我让管理员决定他们是否认为这个问题应该结束,因为 Turivishal 解决方案同样基于那个 Q,但在我看来更清楚.这是他的作品:
<预><代码>[{'$匹配':{'赞助商':'0'}}, {'$graphLookup':{'来自':'请','startWith': '$plid','connectFromField': 'plid','connectToField': '赞助商','depthField': '级别','作为':'孩子'}}, {'$放松':{'path': '$children','preserveNullAndEmptyArrays': 真}}, {'$排序':{'children.level':-1}}, {'$组':{'_id': '$plid',赞助商":{'$first': '$赞助商'},'公司名称': {'$first': '$公司名称'},'孩子们': {'$push': '$children'}}}, {'$addFields':{'孩子们': {'$减少':{'输入':'$儿童','初始值': {'1级,'presentChild': [],'上一个孩子':[]},'在': {'$let':{变量":{'上一个':{'$cond': [{'$eq': ['$$value.level', '$$this.level']}, '$$value.prevChild', '$$value.presentChild']},'当前的': {'$cond': [{'$eq': ['$$value.level', '$$this.level']}, '$$value.presentChild', []]}},'在': {'level': '$$this.level','prevChild': '$$prev','presentChild':{'$concatArrays': ['$$当前', [{'$mergeObjects': ['$$this', {'孩子们': {'$过滤器':{'输入': '$$prev','as': 'e','条件': {'$eq': ['$$e.sponsor', '$$this.plid']}}}}]}]]}}}}}}}}, {'$addFields':{'儿童':'$children.presentChild'}}]您可以使用 $graphLookup 和其他有用的数组运算符,
$match
过滤器只有sponsor
的记录是""
$graphLookup
获取depthFieldlevel
中的子记录和深度数$unwind
解构downline
数组并允许不删除空子元素$sort
按深度级别字段level
按降序排列$group
通过id
字段并重构downline
数组$addFields
现在找到嵌套级别的子级并分配给它的级别,$reduce
迭代downline
数组的循环.- 初始化默认字段
level
默认值为 -1,presentChild
为 [],prevChild
为 [] 用于条件目的 $let
初始化字段:prev
根据条件如果两个level
相等则返回prevChild
否则返回presentChild
current
根据条件如果两个level
相等则返回presentChild
否则返回 []
in
从初始化字段返回level
字段和prevChild
字段presentChild
$filter
downline
从prev
数组返回,将当前对象与downline<合并/code> 数组使用
$mergeObjects
并使用$concatArrays
与 let 的
current
数组连接
$addFields
只返回presentChild
数组,因为我们只需要处理过的数组
db.collection.aggregate([{ $match: { 赞助商: ";} },{$graphLookup:{来自:收藏",startWith: "$_id",connectFromField: "_id",connectToField: "赞助商",深度字段:级别",如:下线"}},{$展开:{路径:$下线",preserveNullAndEmptyArrays: 真}},{ $sort: { "downline.level": -1 } },{$组:{_id: "$_id",赞助商:{ $first: "$sponsor";},公司名称:{ $first:$公司名称";},下线:{ $push:$下线";}}},{$addFields:{下线:{$减少:{输入:$下线",initialValue: { level: -1, presentChild: [], prevChild: [] },在: {$let: {变量:{上一个:{$cond: [{ $eq: ["$$value.level", "$$this.level"] }, "$$value.prevChild", "$$value.presentChild"]},当前的: {$cond: [{ $eq: ["$$value.level", "$$this.level"] }, "$$value.presentChild", []]}},在: {级别:$$this.level",prevChild: "$$prev",礼物孩子:{$concatArrays: [$$current",[{$合并对象:[$$this",{下线:{$过滤器:{输入:$$prev",如:e",cond: { $eq: ["$$e.sponsor", "$$this._id"] }}}}]}]]}}}}}}}},{ $addFields: { downline: "$downline.presentChild";} }])
In my documents, I have the _id, a companyName and a sponsor (which identifies the parent document, by the _id).
For example, I have this first record which has no sponsor (parent)
_id:607536219910ef23e80e0bbe
companyname:"Main Company"
sponsor:"
Then Company 1, where the Main Company is the parent:
_id:607e16760a9d2c16e06bc252
companyname:"Company 1"
sponsor:"607536219910ef23e80e0bbe"
And Company 2, where Company 1 is the parent:
_id:607e187b0a9d2c16e06bc253
companyname:"Company 2"
sponsor:"607e16760a9d2c16e06bc252"
And Company 3, where Company 2 is the parent:
_id:607e1f470a9d2c16e06bc254
companyname:"Company 3"
sponsor:"607e187b0a9d2c16e06bc253"
Im doing a $match to bring the children records for the main company
{
sponsor: '607536219910ef23e80e0bbe'
}
And then I $addFields userid, which is a _Id converted to string. This is to match later with sponsor:
{"userid": { "$toString": "$_id" }}
Now, when I graphLookup I get the child company (Company 2) for Main Company, but I do not get Company 3 as a child of Company 2. I just get Company 1, and Company 2:
Here is my graphLookup
{
from: 'pls',
startWith: "$userid",
connectFromField: 'userid',
connectToField: 'sponsor',
as: 'downline',
maxDepth: 100,
restrictSearchWithMatch: {}
}
Any help will be appreciated.
UPDATE:
As Turivishal said below, the query works, but these are the result I expect:
[{
"_id": "607536219910ef23e80e0bbe",
"companyname": "Main Company",
"downline": [{
"_id": "607e16760a9d2c16e06bc252",
"companyname": "Company 1",
"sponsor": "607536219910ef23e80e0bbe",
"downline": [{
"_id": "607e187b0a9d2c16e06bc253",
"companyname": "Company 2",
"sponsor": "607e16760a9d2c16e06bc252",
"downline": [{
"_id": "607e1f470a9d2c16e06bc254",
"companyname": "Company 3",
"sponsor": "607e187b0a9d2c16e06bc253"
}]
}]
}],
"sponsor": "",
"userId": "607536219910ef23e80e0bbe"
}
SOLUTION BY TURIVISHAL:
As per Turivishal solution, this is the final Pipeline that provides a PERFECT downline/hierarchy/tree view of the recurring query and works perfect with Angular Treeview controls. Thank you very much Turivishal. I believe you should post an answer so I can accept it and it can be useful for others.
His solution is quite similar to the one he proposed, but much better. I ended up creating a new field called PLID which duplicates the _id field, and it works amazingly well. I let the administrators decide if they believe this question should be closed, because again, Turivishal solution is based on that Q, but clearer in my opinion. Here is his work:
[
{
'$match': {
'sponsor': '0'
}
}, {
'$graphLookup': {
'from': 'pls',
'startWith': '$plid',
'connectFromField': 'plid',
'connectToField': 'sponsor',
'depthField': 'level',
'as': 'children'
}
}, {
'$unwind': {
'path': '$children',
'preserveNullAndEmptyArrays': true
}
}, {
'$sort': {
'children.level': -1
}
}, {
'$group': {
'_id': '$plid',
'sponsor': {
'$first': '$sponsor'
},
'companyname': {
'$first': '$companyname'
},
'children': {
'$push': '$children'
}
}
}, {
'$addFields': {
'children': {
'$reduce': {
'input': '$children',
'initialValue': {
'level': -1,
'presentChild': [],
'prevChild': []
},
'in': {
'$let': {
'vars': {
'prev': {
'$cond': [
{
'$eq': [
'$$value.level', '$$this.level'
]
}, '$$value.prevChild', '$$value.presentChild'
]
},
'current': {
'$cond': [
{
'$eq': [
'$$value.level', '$$this.level'
]
}, '$$value.presentChild', []
]
}
},
'in': {
'level': '$$this.level',
'prevChild': '$$prev',
'presentChild': {
'$concatArrays': [
'$$current', [
{
'$mergeObjects': [
'$$this', {
'children': {
'$filter': {
'input': '$$prev',
'as': 'e',
'cond': {
'$eq': [
'$$e.sponsor', '$$this.plid'
]
}
}
}
}
]
}
]
]
}
}
}
}
}
}
}
}, {
'$addFields': {
'children': '$children.presentChild'
}
}
]
You can use $graphLookup and other useful array operators,
$match
filter that records only havesponsor
is""
$graphLookup
to get child records and depth number in depthFieldlevel
$unwind
deconstructdownline
array and allow to not remove empty children$sort
by depth level fieldlevel
in descending order$group
byid
field and reconstructdownline
array$addFields
now find the nested level children and allocate to its level,$reduce
to iterate loop ofdownline
array.- initialize default field
level
default value is -1,presentChild
is [],prevChild
is [] for the conditions purpose $let
to initialize fields:prev
as per condition if bothlevel
are equal then returnprevChild
otherwise returnpresentChild
current
as per condition if bothlevel
are equal then returnpresentChild
otherwise []
in
to returnlevel
field andprevChild
field from initialized fieldspresentChild
$filter
downline
fromprev
array and return, merge current objects withdownline
array using$mergeObjects
and concat withcurrent
array of let using$concatArrays
$addFields
to return onlypresentChild
array because we only required that processed array
db.collection.aggregate([
{ $match: { sponsor: "" } },
{
$graphLookup: {
from: "collection",
startWith: "$_id",
connectFromField: "_id",
connectToField: "sponsor",
depthField: "level",
as: "downline"
}
},
{
$unwind: {
path: "$downline",
preserveNullAndEmptyArrays: true
}
},
{ $sort: { "downline.level": -1 } },
{
$group: {
_id: "$_id",
sponsor: { $first: "$sponsor" },
companyname: { $first: "$companyname" },
downline: { $push: "$downline" }
}
},
{
$addFields: {
downline: {
$reduce: {
input: "$downline",
initialValue: { level: -1, presentChild: [], prevChild: [] },
in: {
$let: {
vars: {
prev: {
$cond: [{ $eq: ["$$value.level", "$$this.level"] }, "$$value.prevChild", "$$value.presentChild"]
},
current: {
$cond: [{ $eq: ["$$value.level", "$$this.level"] }, "$$value.presentChild", []]
}
},
in: {
level: "$$this.level",
prevChild: "$$prev",
presentChild: {
$concatArrays: [
"$$current",
[
{
$mergeObjects: [
"$$this",
{
downline: {
$filter: {
input: "$$prev",
as: "e",
cond: { $eq: ["$$e.sponsor", "$$this._id"] }
}
}
}
]
}
]
]
}
}
}
}
}
}
}
},
{ $addFields: { downline: "$downline.presentChild" } }
])
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