For example, data such as:
{
"name": "Bob"
"friends": [
{
"name": "Lucy",
"age": 18
},
{
"name": "David",
"age": 17
}
]
}
I want to return such a list:["Lucy", "David"]
.
In fact, to put it bluntly, I need to use this returned result to conduct a secondary query, such as the information of Lucy and David.
Limits fields,
db.DATA.find({ }, { "name" : 1 })