LearnBoost/mongoose — Issue #573: Query with non-existent column with 'undefined' value returns all data.
Author: craftgear
Created: 2011-10-23 10:08:57+00:00
State: open

This code returns all data in a collection.

```javascript
Model.find({not_exist_column_name: undefined, function(err, docs){
//err is null, and docs have all data
console.log(err, docs)
})
```

In mongo console, if value is undefined we get:

```
error: { "$err" : "can't have undefined in a query expression", "code" : 13629 }

```

And if column doesn't exist, we simply get nothing.