使用$ and和多个$ or查询MongoDB [英] Query MongoDB with $and and Multiple $or

问题描述

文档中所述，这是不可能的.

As stated in the documentation, this is not possible.

请考虑以下示例:

db.inventory.find( {
    $and : [
        { $or : [ { price : 0.99 }, { price : 1.99 } ] },
        { $or : [ { sale : true }, { qty : { $lt : 20 } } ] }
    ]
} )

此查询将返回所有选择所有文档的位置，

This query will return all select all documents where:

价格字段值等于0.99或1.99，并且 sale字段值等于true或qty字段值小于20.

the price field value equals 0.99 or 1.99, and the sale field value is equal to true or the qty field value is less than 20.

不能使用隐式AND运算来构造此查询，因为它多次使用$ or运算符.

This query cannot be constructed using an implicit AND operation, because it uses the $or operator more than once.

查询这样的东西有什么解决方法?该查询在MongoDB 3.2上不返回任何结果.我已经分别测试了$ or块，并且它们工作正常，但是当它们包装在$ and块中时，还不能正常工作.我以为我没有错误地阅读文档，所以这是行不通的.我唯一的选择是将数据推送到ElasticSearch并在那里查询，但这只是一种解决方法.

What is a workaround to query something like this? This query returns no results on MongoDB 3.2. I have tested the $or blocks separately and they are working fine, but not when they are wrapped in $and block. I assumed I didn't read the documentation incorrectly that this is not supposed to work. The only alternative I have is to push the data to ElasticSearch and query it there instead, but that's also just a workaround.

{
    "$and": [
        {
            "$or": [
                {
                    "title": {
                        "$regex": "^.*html .*$",
                        "$options": "i"
                    }
                },
                {
                    "keywords": {
                        "$regex": "^.*html .*$",
                        "$options": "i"
                    }
                }
            ]
        },
        {
            "$or": [
                {
                    "public": true
                },
                {
                    "domain": "cozybid"
                }
            ]
        }
    ]
}

推荐答案

文档没有说这是不可能的.它只说

the documentation doesn't say that this is impossible. It only says

不能使用隐式AND运算来构造此查询， 因为它多次使用$ or运算符.

This query cannot be constructed using an implicit AND operation, because it uses the $or operator more than once.

这意味着它将起作用:

db.inventory.find( {
    $and : [
        { $or : [ { price : 0.99 }, { price : 1.99 } ] },
        { $or : [ { sale : true }, { qty : { $lt : 20 } } ] }
    ]
} )

但这不会，因为它是隐式 $and ，其中有两个 $or

but this won't, because it's an implicit $and with two $or

db.inventory.find({
        { $or : [ { price : 0.99 }, { price : 1.99 } ] },
        { $or : [ { sale : true }, { qty : { $lt : 20 } } ] }
})

在线试用: mongoplayground.net/p/gL_0gKzGA-u

这是一个带有隐式 $and 的工作案例:

Here is a working case with an implicit $and:

db.inventory.find({ price: { $ne: 1.99, $exists: true } })

我想您面临的问题是在您的收藏集中没有符合您要求的文件

I guess the problem you're facing is that there is no document matching your request in your collection

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