如何检查字段是否存在，如果存在，在 mongodb $in 中获取其值？

Question

I have the below query

db.getCollection('DOCUMENT1').find(                                     
{"FIELD1":           
    {                                                                   
            "$in":[
1234567,
7654321
            ]
    }
}       , "$and": [{
            "FIELD2" : { $exists : true }
    }] 
        ,{"FIELD1" : 1, "FIELD2" : 1} )

When I execute the above query, I get the below error:

Error: Line 9: Unexpected token:

I get only the documents that matches "Field1". Using $in, from the obtained document, I want to check if another field (FIELD2) exists and if exists, I want to display the value of that field. How can I achieve that?

Answer 1

It should be something like this:

db.getCollection('YourCollectionName').find({$and :[{field1: {$in:[1234567, 7654321]}},{field2:{$exists: true}}]},
{field1:1, field2:1, _id:0})

Your query has syntax errors & also $and is an array that takes in multiple filters, which has to be given in place of filterQuery of .find() . Ex:- .find(filterQuery, projectQuery)