Question

我有一个类似这样的文档的收藏集

import { MatDialog } from '@angular/material';
 ....
 public dialog;

 constructor(public dialog: MatDialog) {}

     openSomeModal() {
         const data = {};
         const dialogRef = this.dialog.open(yourModalComponent, {
             data: data,
             width: '400px',
             panelClass: 'any-class',
         });
    }
.....

我只想获取所有嵌入式文档“ StopDetails”。我试图调整下面的代码行，但是我无法在$ query“ StopsDetails”中写什么，以便仅获取StopsDetails嵌入式文档。请帮忙!!!

{
 "_id": ObjectId("5b4dd622d2ccda10c00000f0"),
 "Code": "Route-001",
 "Name": "Karan Nagar - Jawahar Nagar",
 "StopsDetails": [
  {
   "StopId": "cb038446-bbad-5460-79f7-4b138024968b",
   "Code": "Stop- 001",
   "Name": "Lane market",
   "Fee": "600" 
  },
  {
   "StopId": "2502ce2a-900e-e686-79ea-33a2305abf91",
   "Code": "Stop-002",
   "Name": "City center",
   "Fee": "644" 
  }
 ],
  "StopsTiming" :
   [
       ....
   ] 
}

Answer 1

YourModel.findOne({_id:yourId},function(err,result){
    console.log(result); //will return all data 
    console.log(result.StopsDetails); //will retrun your stop details
}

Answer 2

您需要在查询的第二个参数中使用projection

$query = ['_id' => new MongoDB\BSON\ObjectID($this->id)]
$projection = ['StopsDetails' => true]

$cursor = $this->collection->find($query, $projection);

类似于javascript查询

db.collection.find({ '_id': ObjectId }, { 'StopDetails': 1 })

Answer 3

如果要在MongoDB中获取特定的嵌入式字段，则可以使用投影

Projection

尝试mongodb playground

db.col.find({"_id" : ObjectId("5b4dd622d2ccda10c00000f0")},{"StopsDetails" : 1});

投影在PHP mongodb

3 个答案: