检查匹配查询聚合中是否存在字段 mongodb

Question

i have a mongodb collection of events from which i want to get the current availablae events so i am using match query like that

   Event.aggregate([ { $match: { isActive: true, ...matchQuery, startDate:{$lt:today}, endDate:{$gt:today} } },])

the problem is that not all the events in my database have startDate and enDate fields and i want to get those events too, so i want to check if startDate and endDate exists then they should be lt and gt than today if they don't exist and the document match the rest of the query, i want to get it. i tried this way but doesn't work

{ $match: { isEnabled: true, ...matchQuery, startDate ? {startDate:{$lt:today}}, endDate ?  endDate:{$gt:today} } },
  

thank you

Answer 1

So the idea is to fetch all documents where:

1. startDate AND endDate does not exits.

OR

2. today is between the range startDate AND endDate .

Try this:

let today = new Date();

db.events.aggregate([
    {
        $match: {
            isActive: true,
            $or: [
                {
                    startDate: { $exists: false },
                    endDate: { $exists: false }
                },
                {
                    startDate: { $lt: today },
                    endDate: { $gt: today }
                }
            ]
        }
    }
])

Output:

{
    "_id" : ObjectId("..."),
    "isActive" : true,
    "startDate" : ISODate("2021-03-01T00:00:00.000+05:30"),
    "endDate" : ISODate("2021-03-31T00:00:00.000+05:30")
},
{
    "_id" : ObjectId("..."),
    "isActive" : true
}

Test data:

{
    "_id" : ObjectId("..."),
    "isActive" : true,
    "startDate" : ISODate("2021-03-01T00:00:00.000+05:30"),
    "endDate" : ISODate("2021-03-31T00:00:00.000+05:30")
},
{
    "_id" : ObjectId("..."),
    "isActive" : true,
    "endDate" : ISODate("2021-03-31T00:00:00.000+05:30")
},
{
    "_id" : ObjectId("..."),
    "isActive" : true,
    "startDate" : ISODate("2021-03-01T00:00:00.000+05:30")
},
{
    "_id" : ObjectId("..."),
    "isActive" : true
},
{
    "_id" : ObjectId("..."),
    "isActive" : true,
    "startDate" : ISODate("2021-02-01T00:00:00.000+05:30"),
    "endDate" : ISODate("2021-03-03T00:00:00.000+05:30")
}