在$ and之内在$ near附近使用MongoDB [英] Use MongoDB $near within $and

问题描述

我正在尝试搜索位置"，该位置靠近某个位置并符合其他条件，如下所示:

I am trying to search "Places", which are near to a Location AND meet some other criteria as seen here:

var places = Places.find(
{
    $and :
    [
        { categories : placesCategory },

        {
            $or :
            [
                { name    : { $regex : searchQuery, $options : 'i' } },
                { city    : { $regex : searchQuery, $options : 'i' } },
                { country : { $regex : searchQuery, $options : 'i' } }
            ]
        },

        {
            location :
            {
                $near : [ nearLng, nearLat ],
                $maxDistance : 67.15 // radians
            }
        }
    ]
}).fetch();

但是控制台告诉我"$ ear不能在另一个$运算符之内".

However the console tells me that "$near can't be inside another $ operator".

是否可以将$ ear包含在$ and中?

Is there a way to include the $near inside the $and?

或者最佳做法是什么?

推荐答案

您不需要在$ and语句中包含$ near查询.您可以将其放置在外面，否则将无法正常工作.

You don't need to include your $near query inside your $and statement. You can place it outside and it will stil work.

var places = Places.find(
{
    location :
    {
        $near : [ nearLng, nearLat ],
        $maxDistance : 67.15 // radians
    },
    $and :
    [
        { categories : placesCategory },

        {
            $or :
            [
                { name    : { $regex : searchQuery, $options : 'i' } },
                { city    : { $regex : searchQuery, $options : 'i' } },
                { country : { $regex : searchQuery, $options : 'i' } }
            ]
        }
    ]
}).fetch();

但是我不确定您的$ near查询是否正常工作.我更喜欢在坐标上使用'2dsphere'的更具体的查询.例如:

I am however not sure if your $near query is working properly. I prefer a more specific query with an in '2dsphere' on the coordinates. For example:

location:
{
    $near:
    {
        $geometry:
        {
            type: 'Point',
            coordinates: [ nearLng, nearLat ]
        },
        $maxDistance: 67.15 // radians
    }
}

编辑:为了使用上面的查询，请确保您根据此模型保存数据:

EDIT: In order to use the above query, make sure you are saving you data according to this model:

location: {
    type: {
        type: String,
        enum: 'Point',
        default: 'Point'
    },
    coordinates: {
        type: [Number],
        default: [0,0],
        index: '2dsphere'
    }
}

当您想在矩形内查找位置时，可能需要 $ box 运算符.这是一个搜索查询示例(请注意，我没有经验.您可能需要更改模型和/或添加索引以改进查询):

When you want to find places inside a rectangle, you wil probably need the $box operator. This is an example search query (please note, I have no experience with it. You might need to change your model and/or add an index to improve the query):

location: {
     $geoWithin: {
        $box: [
          [ <bottom left coordinates> ],
          [ <upper right coordinates> ]
        ]
     }
  }
}

让我知道这是否有帮助！

Let me know if this helps!

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