Mongoose query with undefined

Question

Mongoose query with undefined

I am trying to use mongoose to construct a query equivalent to this SQL:

select * from problems where tutorialNumber is not null

I've tried:

    var q = Problem.find().where('tutorialNumber').ne(undefined);
    q.exec(callback);

It returned an error: CastError: Cast to string failed for value "undefined" at path "tutorialNumber"

What is the right way to do that?

node.js
mongoose

Answer 1

There are several syntax options. I believe your code is OK other than you should use null instead of undefined. I prefer the style that is a little closer to normal mongo shell:

Problem.find({tutorialNumber: {$ne: null}}, callback);

or you can do

Problem.find().ne('tutorialNumber', null).exec(callback);

But I believe the way you are using where and ne are also correct.

However, the CastError can mean there's a problem in your schema (could be trying to nest models instead of nesting schema).

Answer 2

Thanks for the replies. I found another way to do it:

var q = Problem.find().exists('tutorialNumber', true);
q.exec(callback);