# Querying

Blini uses an immutable version of [mquery](https://github.com/aheckmann/mquery) to build MongoDB queries.

Comparing to Mongoose, Blini queries doesn't have a `.then` and promise interface, you have to explicitly call '.exec()'.

## Execute the query

`Query.exec(): Promise<List>`

`.exec` returns a promise resolving with a list of all documents

```javascript
Post.where('clicks').gt(999).exec()
    .then(function(list) {

    });
```

## Stream documents

`Query.stream(): ReadableStream`

`.exec` returns a list of all documents by accumulating results from MongoDB.

```javascript
Post.where('clicks').gt(999).exec()
    .then(function(list) {
        // No more results
    }, function(err) {
        // Error
    }, function(post) {
        // Receive a document
    });
```

## Query one document

`Query.findOne(): Query`

```javascript
Post.findOne({ _id: '...' }).exec()
    .then(function(post) {

    });``
```