包含与不包含:in、nin
> db.accounts.find({"name":{$in:["alice2"]}}).pretty()
{ "_id" : "account1", "name" : "alice2", "balance" : 100 }
{
"_id" : ObjectId("5d7f43abaecbd2bc0fa821b7"),
"name" : "alice2",
"balance" : 100
}
> db.accounts.find({"name":{$in:> db.accounts.find({"name":{$in:["alice2"]}}).pretty()
{ "_id" : "account1", "name" : "alice2", "balance" : 100 }
{
"_id" : ObjectId("5d7f43abaecbd2bc0fa821b7"),
"name" : "alice2",
"balance" : 100
}
> db.accounts.find({"name":{$in: