Check that Field Exists with MongoDB

manpreet Best Answer 2 years ago

So I'm attempting to find all records who have a field set and isn't null.

I try using $exists, however according to the MongoDB documentation, this query will return fields who equal null.

$exists does match documents that contain the field that stores the null value.

So I'm now assuming I'll have to do something like this:

db.collection.find({ "fieldToCheck" : { $exists : true, $not : null } })

Whenever I try this however, I get the error [invalid use of $not] Anyone have an idea of how to query for this?

manpreet 2 years ago

Use $ne (for "not equal")

db.collection.find({ "fieldToCheck": { $exists: true, $ne: null } })