我在我的收藏中有一个记录,我想获取id为1的人的详细信息.但我得到的细节是2次而不是1次.
db.mycollection.insert({"person" : [ { "id":1, "details" : { "name" : "Aswini", "Age" : 10 }}, { "id":2, "details" : { "name" : "Mahesh", "Age" : 11}}]})
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然后跑
> db.mycollection.findOne({"person.id":1},{"person.details":1,"_id":0})
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结果是:
{
"person" :
[
{
"details" :
{
"name" : "Aswini",
"Age" : 10
}
},
{
"details" :
{
"name" : "Mahesh",
"Age" : 11
}
}
]
}
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但我需要如下:
{
"person" : [
{
"details" : {
"name" : "Aswini",
"Age" : 10
}
}
]
} …Run Code Online (Sandbox Code Playgroud)