mongoDB查询文档内的文档

Question

我正在寻找mongodb查询来从文档内的文档中检索结果。我有这样的集合：

{
    "_id" : ObjectId("59e6ea30ef03f811538bagd4"),
    "_class" : "xyz",
    "name" : "Test1",
    "attributes" : [ 
        {
            "attributeName" : "Country",
            "includedAttributes" : [ 
                {
                    "_id" : ObjectId("59ddffe7d1f2f34eb9d32dcf"),
                    "attributeValue" : "United States",
                    "attributeName" : "Country"
                }
            ]
        }
    ]
},
{
    "_id" : ObjectId("59e6ea30ef03f811538bxed4"),
    "_class" : "xyz",
    "name" : "Test2",
    "attributes" : [ 
        {
            "attributeName" : "Country",
            "includedAttributes" : [ 
                {
                    "_id" : ObjectId("59ddffe7d1f2g34eb9d32dcf"),
                    "attributeValue" : "Buffalo",
                    "attributeName" : "City"
                }
            ]
        }
    ]
},
{
    "_id" : ObjectId("59e6ea30ef03f811538baef4"),
    "_class" : "xyz",
    "name" : "Test3",
    "attributes" : [ 
        {
            "attributeName" : "City",
            "includedAttributes" : [ 
                {
                    "_id" : ObjectId("59ddffe7h1f2e34eb9d32dcf"),
                    "attributeValue" : "Chicago",
                    "attributeName" : "City"
                }
            ]
        }
    ]
}

我希望查询此条件inludedAttributes {attributeName：Country and attributeValue：United States}或inludedAttributes {attributeName：City and attributeValue：Buffalo}。

我尝试了以下查询，但它给了我零结果：

db.getCollection('collection1').find({
"$or" : [ { "attributes" : { "$elemMatch" : { "includedAttributes" : { "$elemMatch" : { "attributeName" : "Country"}} , "$and" : [ { "attributeValue" : "United States"}]}}},
{ "attributes" : { "$elemMatch" : { "includedAttributes" : { "$elemMatch" : { "attributeName" : "City"}} , "$and" : [ { "attributeValue" : "Buffalo"}]}}} ]})