Streaming Queries

[wbyoung]

For large data sets, it'd be nice to allow streaming data queries. For instance:

var query = Article.objects.where({ authorId: 5 });
query.on('data', function(article) {
  // handle single record
});
query.on('end', function() {
  // all records handled
});
query.execute().then(function(result) {
  expect(result).to.not.exist;
});

Because streaming would be used for large data sets, the expectation would be that when adding a data event handler, the query would no longer aggregate the results (consuming memory). We could make this something that you could disable:

var query = Article.objects.where({ authorId: 5 }).aggregate();
query.on('data', function(article) {
  // handle single record
});
query.execute().then(function(result) {
  expect(result).to.eql([article1, article2, article3]);
});