如何在mongo中的嵌套文档中插入文档或字段

Question

我想要一个名为system的集合，在该集合下有一个名为sub_systems的文档，在其下有三个名为high mid＆low的文档。每个高，中和低分别包含多个文档，如下所示

systems: {
           sub_system_1 : {
                            high :{ {task1},
                                    {task2},
                                    .......
                                  },                                
                            mid  :{ {task1},
                                    {task2},
                                    .......
                                  },
                            low :{ {task1},
                                    {task2},
                                    .......
                                  },
                          },
           sub_system_2 : {
                            high :{ {task1},
                                    {task2},
                                    .......
                                  },                                
                            mid  :{ {task1},
                                    {task2},
                                    .......
                                  },
                            low :{ {task1},
                                    {task2},
                                    .......
                                  },
                          },
           ............
         }

因此，下面是我的问题1.我将如何创建此类嵌套文档。2.如何在系统集合中插入新的子系统。3.如何在子系统文件下插入新的优先级（高，中，低）。4.如何在特定子系统和特定优先级（高，低，中）文档中插入新任务

我想使用mongo shell以及perl mongodb来了解这一点

Answer 1

使用外壳

1.如何创建此类嵌套文档

db.systems.insert( [{"name": "sub_system_1", "data" : {"high" :["task1","task2"], "mid": ["task1","task2"], "low" : ["task1","task2"]}},{"name": "sub_system_2" ,"data": {"high" :["task1","task2"], "mid": ["task1","task2"], "low" : ["task1","task2"]}}])

2.如何在系统集合中插入新的子系统

db.systems.insert( {"name": "sub_system_3", "data" : {"high" :["task1","task2"], "mid": ["task1","task2"], "low" : ["task1","task2"]}})

3.如何在子系统文件下插入新的优先级（高，中，低）

// First you need to find the document using the name field
var sub_system_1 = db.systems.findOne({"name":"sub_system_1"})
// set your new priority
sub_system_1.data.new_priority = [ "task1", "task2" ]
// Save updated document 
db.systems.save(sub_system_1)

您还可以使用updateOne调用在一条语句中进行更新，请参阅以下文档 https://docs.mongodb.com/manual/reference/method/db.collection.updateOne/#db.collection.updateOne

4.如何将新任务插入到特定的子系统中并以特定的优先级（高，低，中）文档

// First you need to find the document using the name field
var sub_system_1 = db.systems.findOne({"name":"sub_system_1"})
// Now we add a new task to priority low
sub_system_1.data.low[sub_system_1.data.low.length] = "task3"
// Save updated document 
db.systems.save(sub_system_1)

使用Perl MongoDB

#!/usr/bin/perl

use MongoDB::Connection;

my $mongodb_dbhost = 'mongodb.co.za';
my $mongodb_dbname = 'systems_production';
my $mongodb_dbtable = 'systems';

my $connection   =  MongoDB::Connection->new(host => $mongodb_dbhost);

my $collection = $connection->$mongodb_dbname->$mongodb_dbtable;

1.如何创建此类嵌套文档

my $data = $collection->insert( [
    {
       "name": "sub_system_1", "data" : {"high" :["task1","task2"], "mid":     ["task1","task2"], "low" : ["task1","task2"]}
},
{
    "name": "sub_system_2" ,"data": {"high" :["task1","task2"], "mid":    ["task1","task2"], "low" : ["task1","task2"]}
}
  ]); 

2.如何在系统集合中插入新的子系统

  $data = $collection->insert({
      "name": "sub_system_3", 
   "data" : {"high" :["task1","task2"], "mid": ["task1","task2"], "low" :     ["task1","task2"]}
  });

3.如何在子系统文件下插入新的优先级（高，中，低）

my $sub_system_1 = $connection->$mongodb_dbname->$mongodb_dbtable->find_one({'name' => 'sub_system_1'});
$sub_system_1->{data}->{new_priority} = [ "task1", "task2" ];
$collection->save($sub_system_1);

4.如何在特定子系统和特定优先级（高，低，中）文档中插入新任务

my $sub_system_1 = $connection->$mongodb_dbname->$mongodb_dbtable->find_one({'name' => 'sub_system_1'});
 $sub_system_1->{data}->{low}->[scalar(@$sub_system_1->{data}->{low})] = "task3";
 $collection->save($sub_system_1);