Question

我在查询名为Geolytix Supermarkets January 2015 update的数据集时遇到问题问题是我运行的查询要么返回所有结果，要么根本没有结果。这是数据集的快照：

{"type":"FeatureCollection","features":
[{"type":"Feature","properties":{"OBJECTID":10001,"GLUID":1010010014,"Retailer":"The Co-operative Group",
    "Fascia":"The Co-operative Food","StoreName":"New Road","Add1":"650 Oldham Road",
    "Add2":"Failsworth", "Town":"Manchester","Locality":"Failsworth","Postcode":"M359DU",
    "LongWGS84":-2.14949,"LatWGS84":53.515,"EastingBNG":390185,"NorthingBNG":402050,"PQIflag":2},"geometry":
    {"type":"Point","coordinates":[-2.1494900003123174,53.51499999980253]}},

  {"type":"Feature","properties":{"OBJECTID":10002,"GLUID":1010010015,"Retailer":"The Co-operative Group",
          "Fascia":"The Co-operative Food","StoreName":"Mobberley","Add1":"85 Town Lane",
       "Add2":null,"Town":"Mobberley","Locality":null,"Postcode":"WA167HH","LongWGS84":-2.32905,"LatWGS84":53.3136,
        "EastingBNG":378175,"NorthingBNG":379680,"PQIflag":2},"geometry":
     {"type":"Point","coordinates":[-2.329049999711877,53.31359999998222]}},

据我所知，这个数据结构是数组中的嵌入/嵌套文档，以便检索我必须访问数组和文档的数据。为此，我使用点表示法尝试了这些查询：

db.January_2015.find ({"features.properties.Retailer":"The Co-operative Group"});

这个很清楚地返回整个数据集，这是不正确的。然后我尝试了这些：

db.January_2015.find ({"features.properties: {"OBJECTID":10001}});

db.January_2015.find ({"features.properties: {"Retailer":"The Co-operative Group}});

db.January_2015.find ({"features.properties": {$elemMatch: {"OBJECTID":10001, "GLUID": 1010010014}}});

这三个人根本没有任何回报。我已经研究了文档，根据它，至少有一种方法应该有效。我在这做错了什么？我考虑过使用聚合框架，但对于像这样的简单查询来说，这似乎过于复杂。有人可以确认我是否尝试过正确的方法，或者我是否必须使用聚合？

MongoDB查询数组中的嵌入文档而不返回结果

0 个答案: