如何编写一个从JavaScript数组中找到字段匹配的MongoDB查询

Question

I'm trying to put together a MongoDB query that will return results where a field equals a value that is present in a JavaScript array. I've put together the following code so far but it isn't working. I would like the number field in the collection to find a match within the versions array. I'm thinking that my "list" part using the $map under the first $project is wrong.

//example data
var versions = ['v1', 'v2', 'v3'];

function getResults(versions) {

    var query =
    {
        "db": "db-name",
        "collection": "collection-name",
        "query":
        [
            {
                $match: {
                    time:  getStartTime(),
                }
            },
            {
                $project:
                {
                    number: "$number",
                    session_id: "$session_id",
                    round_id: "$_id",
                    "list": {
                        "$map": {
                            "input": { "$filter": {
                                "input": versions,
                                "as": "versions",
                                "cond": {
                                    "$eq": [ "$$versions.value", "$number" ]
                                }
                            }},
                            "as": "versions",
                            "in": "$$versions.value"
                        }
                    }

                }
            },
            {
                $group:
                {
                    _id: "$session_id",
                    number: { $first: "$list" },
                    rounds: { $addToSet: "$round_id" }
                }
            },
            {
                $project:
                {
                    number: "$number",
                    rounds: "$rounds"
                }
            }
        ]
    }
    return query;
}

Answer 1

Can you provide more info about you are triyng to do?

Maybe you can use filter by javascript array .

Here is an example code:

function isBigEnough(value) {
  return value >= 10;
}
var filtered = [12, 5, 8, 130, 44].filter(isBigEnough);
// filtered is [12, 130, 44]

Maybe filter could be useful for you.