MongoDB : find value in Array with multiple criteria

Question

I have the following documents:

{_id : 1, numbers : [-1000, 1000]}
{_id : 2, numbers : [5]}

I'm trying to get a query that will find a document that has a value in the numbers array that is between -10 and 10 (in this case, _id : 2). However, when I try the following:

db.foo.find({numbers : $and : [{$gt : -10},{$lt : 10}]})

it returns all documents. Is this possible to do without map-reduce? Thanks, -JWW

Answer 1

You can use $elemMatch to check if an element in an array matches a specified match expression.

In this case, you can use it to get a document whose numbers array has an element that is between -10 and 10:

   db.foo.find( { numbers : { $elemMatch : { $gt : -10 , $lt : 10 } } } );

This will just return the _id : 2 document.