MongoDB&Mongoose查询返回null表示聚合$或搜索字段不匹配,返回单个搜索或省略未定义的值

$or 操作员被视为 $and

我有以下要查询的收集文档:

{
    "_id": {
        "$oid": "5bd0d709ff8eef5d5325090f"
    },
    "audienceTrackingID": "3e66c213-fe0b-4096-a99c-558a6c349b4b",
    "mainframeTrackingID": null,
    "partner1TrackingID": "85c5f168-08da-44d3-bbef-fbb3b8392ded",
    "__v": 0,
    "contentFocus": "Cooking",
    "ipRange": [
        "29.142.127.151"
    ]
}

使用以下查询:

console.log(req.headers['x-original-ip']) // '29.142.127.151'
console.log(req.headers['x-audience-tracking-id']) // undefined
console.log(req.headers['x-partner-1-tracking-id']) // "85c5f168-08da-44d3-bbef-fbb3b8392ded"

const clientMatch = await Client.findOne({
    $or: [{ 
        ipRange: req.headers['x-original-ip'],  
        audienceTrackingID: req.headers['x-audience-tracking-id'],
        partner1TrackingID: req.headers['x-partner-1-tracking-id'],
    }]
})

console.log(clientMatch) // null

有些令人费解,比如查询单个字段,以及删除实际查询中参数未定义的查询( req.headers['x-audience-tracking-id'] )将产生结果(这让我想知道,为什么这就像一个AND,当一个queryfield失败时给我空值??)

// ALL QUERIES HIT AND RETURN A MATCH:

const tryThis = await Client.findOne({partner1TrackingID: req.headers['x-partner-1-tracking-id']})
const ipMatch = await Client.findOne({ipRange: req.headers['x-original-ip']})
const clientMatch = await Client.findOne({
    $or: [{ 
        ipRange: req.headers['x-original-ip'],  
        partner1TrackingID: req.headers['x-partner-1-tracking-id'],
    }]
})

这对我来说毫无意义。当其他字段匹配时,为什么我需要省略$或运算符中可能不匹配的字段以获得命中?