使用Go获取MongoDB中所有模型树子节点
来源:stackoverflow
时间:2024-02-25 09:42:29 467浏览 收藏
在IT行业这个发展更新速度很快的行业,只有不停止的学习,才不会被行业所淘汰。如果你是Golang学习者,那么本文《使用Go获取MongoDB中所有模型树子节点》就很适合你!本篇内容主要包括##content_title##,希望对大家的知识积累有所帮助,助力实战开发!
问题内容
我在 mongodb 中收集数据。
我的数据是在模型树中构建的,子节点
和父节点
之间的关系是属性parentid
。
这是我的数据架构
这是我的示例数据
{"_id":{"$oid":"5ebd05b52f3700008500220b"},"username":"dhbk","password":"123456","lastname":"dhbk","useremail":"[email protected]","usertel":"0907111001","userdate":"2020-05-05","userstatus":"active","userparentid":null,"comid":"dhbk","comdepartment":"dhbk","usercode":"dhbk_0001","usertype":"admin_com"} {"_id":{"$oid":"5ebd05b52f3700008500220c"},"username":"khoa_dien","password":"123456","lastname":"khoa_dien","useremail":"[email protected]","usertel":"0907111002","userdate":"2020-05-05","userstatus":"active","userparentid":"dhbk","comid":"dhbk","comdepartment":"khoa_dien","usercode":"dhbk_0002","usertype":"user_com"} {"_id":{"$oid":"5ebd05b52f3700008500220d"},"username":"khoa_xd","password":"123456","lastname":"khoa_xd","useremail":"[email protected]","usertel":"0907111003","userdate":"2020-05-05","userstatus":"active","userparentid":"dhbk","comid":"dhbk","comdepartment":"khoa_xd","usercode":"dhbk_0003","usertype":"user_com"} {"_id":{"$oid":"5ebd05b52f3700008500220e"},"username":"khoa_cntt","password":"123456","lastname":"khoa_cntt","useremail":"[email protected]","usertel":"0907111004","userdate":"2020-05-05","userstatus":"active","userparentid":"dhbk","comid":"dhbk","comdepartment":"khoa_cntt","usercode":"dhbk_0004","usertype":"user_com"} {"_id":{"$oid":"5ebd05b52f3700008500220f"},"username":"bomon_tudong","password":"123456","lastname":"bomon_tudong","useremail":"[email protected]","usertel":"0907111005","userdate":"2020-05-05","userstatus":"active","userparentid":"khoa_dien","comid":"dhbk","comdepartment":"khoa_dien","usercode":"dhbk_0005","usertype":"user_com"} {"_id":{"$oid":"5ebd05b52f37000085002210"},"username":"bomon_vienthong","password":"123456","lastname":"bomon_vienthong","useremail":"[email protected]","usertel":"0907111006","userdate":"2020-05-05","userstatus":"active","userparentid":"khoa_dien","comid":"dhbk","comdepartment":"khoa_dien","usercode":"dhbk_0006","usertype":"user_com"} {"_id":{"$oid":"5ebd05b52f37000085002211"},"username":"bomon_hethong","password":"123456","lastname":"bomon_hethong","useremail":"[email protected]","usertel":"0907111007","userdate":"2020-05-05","userstatus":"active","userparentid":"khoa_dien","comid":"dhbk","comdepartment":"khoa_dien","usercode":"dhbk_0007","usertype":"user_com"} {"_id":{"$oid":"5ebd05b52f37000085002212"},"username":"bomon1_xd","password":"123456","lastname":"bomon1_xd","useremail":"[email protected]","usertel":"0907111008","userdate":"2020-05-05","userstatus":"active","userparentid":"khoa_xd","comid":"dhbk","comdepartment":"khoa_xd","usercode":"dhbk_0008","usertype":"user_com"} {"_id":{"$oid":"5ebd05b52f37000085002213"},"username":"bomon2_xd","password":"123456","lastname":"bomon2_xd","useremail":"[email protected]","usertel":"0907111009","userdate":"2020-05-05","userstatus":"active","userparentid":"khoa_xd","comid":"dhbk","comdepartment":"khoa_xd","usercode":"dhbk_0009","usertype":"user_com"} {"_id":{"$oid":"5ebd05b52f37000085002214"},"username":"bomon3_xd","password":"123456","lastname":"bomon3_xd","useremail":"[email protected]","usertel":"0907111010","userdate":"2020-05-05","userstatus":"active","userparentid":"khoa_xd","comid":"dhbk","comdepartment":"khoa_xd","usercode":"dhbk_0010","usertype":"user_com"} {"_id":{"$oid":"5ebd05b52f37000085002215"},"username":"truongkhoa_bmvt","password":"123456","lastname":"truongkhoa_bmvt","useremail":"[email protected]","usertel":"0907111011","userdate":"2020-05-05","userstatus":"active","userparentid":"bomon_vienthong","comid":"dhbk","comdepartment":"bomon_vienthong","usercode":"dhbk_0011","usertype":"user_com"} {"_id":{"$oid":"5ebd05b52f37000085002216"},"username":"phokhoa_bmvt","password":"123456","lastname":"phokhoa_bmvt","useremail":"[email protected]","usertel":"0907111012","userdate":"2020-05-05","userstatus":"active","userparentid":"bomon_vienthong","comid":"dhbk","comdepartment":"bomon_vienthong","usercode":"dhbk_0012","usertype":"user_com"} {"_id":{"$oid":"5ebd05b52f37000085002217"},"username":"thuky_bmvt","password":"123456","lastname":"thuky_bmvt","useremail":"[email protected]","usertel":"0907111013","userdate":"2020-05-05","userstatus":"active","userparentid":"bomon_vienthong","comid":"dhbk","comdepartment":"bomon_vienthong","usercode":"dhbk_0013","usertype":"user_com"} {"_id":{"$oid":"5ebd05b52f37000085002218"},"username":"gv_bmvt","password":"123456","lastname":"gv_bmvt","useremail":"[email protected]","usertel":"0907111014","userdate":"2020-05-05","userstatus":"active","userparentid":"bomon_vienthong","comid":"dhbk","comdepartment":"bomon_vienthong","usercode":"dhbk_0014","usertype":"user_com"} {"_id":{"$oid":"5ebd05b52f37000085002219"},"username":"sv1_bmvt","password":"123456","lastname":"sv1_bmvt","useremail":"[email protected]","usertel":"0907111015","userdate":"2020-05-05","userstatus":"active","userparentid":"gv_bmvt","comid":"dhbk","comdepartment":"bomon_vienthong","usercode":"dhbk_0015","usertype":"user_com"} {"_id":{"$oid":"5ebd05b52f3700008500221a"},"username":"sv2_bmvt","password":"123456","lastname":"sv2_bmvt","useremail":"[email protected]","usertel":"0907111016","userdate":"2020-05-05","userstatus":"active","userparentid":"gv_bmvt","comid":"dhbk","comdepartment":"bomon_vienthong","usercode":"dhbk_0016","usertype":"user_com"} {"_id":{"$oid":"5ebd05b52f3700008500221b"},"username":"sv3_bmvt","password":"123456","lastname":"sv3_bmvt","useremail":"[email protected]","usertel":"0907111017","userdate":"2020-05-05","userstatus":"active","userparentid":"gv_bmvt","comid":"dhbk","comdepartment":"bomon_vienthong","usercode":"dhbk_0017","usertype":"user_com"} {"_id":{"$oid":"5ebd05b52f3700008500221c"},"username":"sv4_bmvt","password":"123456","lastname":"sv4_bmvt","useremail":"[email protected]","usertel":"0907111018","userdate":"2020-05-05","userstatus":"active","userparentid":"gv_bmvt","comid":"dhbk","comdepartment":"bomon_vienthong","usercode":"dhbk_0018","usertype":"user_com"} {"_id":{"$oid":"5ec642b2412b0000e70021a5"},"username":"khoa_kt","password":"123456","lastname":"khoa_kt","useremail":"[email protected]","usertel":"0907111002","userdate":"2020-05-05","userstatus":"active","userparentid":"dhkt","comid":"dhbk","comdepartment":"khoa_kt","usercode":"dhkt_0002","usertype":"user_com"} {"_id":{"$oid":"5ec642b2412b0000e70021a8"},"username":"bomon_ktdoanhnghiep","password":"123456","lastname":"bomon_ktdoanhnghiep","useremail":"[email protected]","usertel":"0907111005","userdate":"2020-05-05","userstatus":"active","userparentid":"khoa_kt","comid":"dhbk","comdepartment":"khoa_kt","usercode":"dhkt_0005","usertype":"user_com"} {"_id":{"$oid":"5ece3517b8d5570916d013f6"},"username":"sv5_bmvt","password":"123","lastname":"sv5_bmvt","useremail":"[email protected]","usertel":"0907111019","userdate":"2020-05-14","userstatus":"active","userparentid":"gv_bmvt","comid":"dhbk","comdepartment":"bomon_vienthong","usercode":"dhbk_0019","usertype":"user_com"} {"_id":{"$oid":"5eddf0a9b8d5570916dae6ff"},"username":"sv6_bmvt","password":"123456","lastname":"sv6_bmvt","useremail":"[email protected]","usertel":"0907111020","userdate":"2020-06-08","userstatus":"active","userparentid":"gv_bmvt","comid":"dhbk","comdepartment":"bomon_vienthong","usercode":"dhbk_0019","usertype":"user_com"}
现在我想获取特定父节点的所有子节点。比如我想获取dhbk节点
的所有子节点。
我已经完成了 mongodb shell 来查询这个需求。
这是我的 mongodb shell
var descendants=[] var stack=[]; var item = db.users.findone({username:"dhbk"}); stack.push(item); while (stack.length>0){ var currentnode = stack.pop(); var children = db.users.find({userparentid:currentnode.username}); while(true === children.hasnext()) { var child = children.next(); descendants.push(child.username); stack.push(child); } } descendants.join(",")
它有效并显示了正确的结果。这是我的输出结果
khoa_dien,khoa_xd,khoa_cntt,bomon1_xd,bomon2_xd,bomon3_xd,bomon_tudong,bomon_vienthong,bomon_hethong,truongkhoa_bmvt,phokhoa_bmvt,thuky_bmvt,gv_bmvt,sv1_bmvt,sv2_bmvt,sv3_bmvt,sv4_bmvt,sv5_bmvt,sv6_bmvt
然后我编写 go 代码来实现这个 mongodb shell。
这是我的代码
package main import ( "context" "fmt" "strings" "time" "go.mongodb.org/mongo-driver/bson" "go.mongodb.org/mongo-driver/mongo" "go.mongodb.org/mongo-driver/mongo/options" ) func main() { GetAllChildOfNode("DHBK") } func GetAllChildOfNode(node string) error { ctx, _ := context.WithTimeout(context.Background(), 10*time.Second) client, err := mongo.Connect(ctx, options.Client().ApplyURI("URI string")) if err != nil { return err } defer client.Disconnect(ctx) database := client.Database("users") users := database.Collection("users") var descendants []string var stack []string err = users.FindOne(ctx, bson.M{"username": "DHBK"}).Decode(&stack) leng := len(stack) for leng > 0 { //I HaVE TROUBLE HERE currentnode := stack. } return nil }
但是我在使用 go 将 push
、pop
方法和 while loop
作为 mongodb shell 实现时遇到了麻烦。
解决方案
看看您是否同意 $graphLookup 的限制。
如果是这样,您可以在单个聚合查询中在数据库端执行此操作:
db.collection_name.aggregate([ {$match: {username: "DHBK"}}, // select root document { $graphLookup: { // load the tree as embedded docs from: "collection_name", startWith: "$username", connectFromField: "username", connectToField: "userparentid", as: "descendants", } }, {$project: { // add root element if needed descendants: {$concatArrays: [["$$ROOT"], "$descendants"] } }}, {$unwind: "$descendants"}, // final formatting steps {$replaceRoot: {newRoot: "$descendants"}}, {$project: {descendants:0}} ])
今天带大家了解了的相关知识,希望对你有所帮助;关于Golang的技术知识我们会一点点深入介绍,欢迎大家关注golang学习网公众号,一起学习编程~
声明:本文转载于:stackoverflow 如有侵犯,请联系study_golang@163.com删除
相关阅读
更多>
-
502 收藏
-
502 收藏
-
501 收藏
-
501 收藏
-
501 收藏
最新阅读
更多>
-
139 收藏
-
204 收藏
-
325 收藏
-
477 收藏
-
486 收藏
-
439 收藏
-
357 收藏
-
352 收藏
-
101 收藏
-
440 收藏
-
212 收藏
-
143 收藏
课程推荐
更多>
-
- 前端进阶之JavaScript设计模式
- 设计模式是开发人员在软件开发过程中面临一般问题时的解决方案,代表了最佳的实践。本课程的主打内容包括JS常见设计模式以及具体应用场景,打造一站式知识长龙服务,适合有JS基础的同学学习。
- 立即学习 542次学习
-
- GO语言核心编程课程
- 本课程采用真实案例,全面具体可落地,从理论到实践,一步一步将GO核心编程技术、编程思想、底层实现融会贯通,使学习者贴近时代脉搏,做IT互联网时代的弄潮儿。
- 立即学习 508次学习
-
- 简单聊聊mysql8与网络通信
- 如有问题加微信:Le-studyg;在课程中,我们将首先介绍MySQL8的新特性,包括性能优化、安全增强、新数据类型等,帮助学生快速熟悉MySQL8的最新功能。接着,我们将深入解析MySQL的网络通信机制,包括协议、连接管理、数据传输等,让
- 立即学习 497次学习
-
- JavaScript正则表达式基础与实战
- 在任何一门编程语言中,正则表达式,都是一项重要的知识,它提供了高效的字符串匹配与捕获机制,可以极大的简化程序设计。
- 立即学习 487次学习
-
- 从零制作响应式网站—Grid布局
- 本系列教程将展示从零制作一个假想的网络科技公司官网,分为导航,轮播,关于我们,成功案例,服务流程,团队介绍,数据部分,公司动态,底部信息等内容区块。网站整体采用CSSGrid布局,支持响应式,有流畅过渡和展现动画。
- 立即学习 484次学习