MongoDB find（）。count（）-语法错误：缺少：在属性ID（shell）之后：1

Question

Have a .json data-supplied collection of tweets..

Looking to count Delete-Requests in Sessions:

db.tweets.find({"delete"}).count()

And this syntax is incorrect because SyntaxError: missing : after property id (shell):1

Have more find() and count() operations to perform, but the error is consistent.

This is what a Delete-Request looks like (where " … " is either a series of letters and/or numbers) :

{
    "_id" : ObjectId("…"),
    "delete" : {
        "status" : {
            "id" : NumberLong("…"),
            "user_id" : …,
            "id_str" : "…",
            "user_id_str" : "…"
        }
    }
}

Answer 1

In the find() function you have to pass an object. You missed the key/value, because {"delete"} isn't a valid object.

I think that you want to get the number of documents that have the delete key. For this you have to use $exists operator with true value.

db.tweets.find({ "delete": { $exists: true } }).count();

or directly

db.tweets.count({ "delete": { $exists: true } });

From documentation :

$exists selects the documents that contain the field if is true. If is false, the query only returns the documents that do not contain the field. Documents that contain the field but has the value null are not returned.