Documents can be retrieved through find
, findOne
and findById
. These
methods are executed on your Model
s.
Model.find(query, fields, options, callback)
// fields and options can be omitted
Model.find({ 'some.value': 5 }, function (err, docs) {
// docs is an array
});
Model.find({}, ['first', 'last'], function (err, docs) {
// docs is an array of partially-`init`d documents
// defaults are still applied and will be "populated"
})
Same as Model#find
, but only receives a single document as second parameter:
Model.findOne({ age: 5}, function (err, doc){
// doc is a Document
});
Same as findOne
, but receives a value to search a document by their _id
key. This value is subject to casting, so it can be a hex string or a proper
ObjectId.
Model.findById(obj._id, function (err, doc){
// doc is a Document
});
Counts the number of documents matching conditions
.
Model.count(conditions, callback);
Removes documents matching conditions
.
Model.remove(conditions, callback);
Finds distinct values of field
for documents matching conditions
.
Model.distinct(field, conditions, callback);
Creates a Query for this model. Handy when expressing complex directives.
Model
.where('age').gte(25)
.where('tags').in(['movie', 'music', 'art'])
.select('name', 'age', 'tags')
.skip(20)
.limit(10)
.asc('age')
.slaveOk()
.hint({ age: 1, name: 1 })
.run(callback);
Sometimes you need to query for things in mongodb using a JavaScript expression. You can do so via find({$where: javascript}), or you can use the mongoose shortcut method $where via a Query chain or from your mongoose Model.
Model.$where('this.firstname === this.lastname').exec(callback)
Updates all documents matching conditions
using the update
clause. All
update
values are casted to their appropriate types before being sent.
var conditions = { name: 'borne' }
, update = { $inc: { visits: 1 }}
, options = { multi: true };
Model.update(conditions, update, options, callback)
Note: for backwards compatibility, all top-level update
keys that are
not $atomic operation names are treated as $set
operations. Example:
var query = { name: 'borne' };
Model.update(query, { name: 'jason borne' }, options, callback)
// is sent as
Model.update(query, { $set: { name: 'jason borne' }}, options, callback)
Each of these methods returns a Query.
If you don't pass a callback to these methods, the Query can be continued to be
modified (such as adding options, fields, etc), before it's exec
d.
var query = Model.find({});
query.where('field', 5);
query.limit(5);
query.skip(100);
query.exec(function (err, docs) {
// called when the `query.complete` or `query.error` are called
// internally
});