Mongoose, find, return specific properties

I have this get call:

exports.getBIMFromProject = function(req, res){
mongoose.model('bim').find({projectId: req.params['prj_id']}, function(err, bim){
if(err){
console.error(err);
res.send(500)
}
res.send(200, bim);
});
};

Where do I specify which properties I want to return? Can't find it in the docs. The above returns the entire object. I only want a few properties returned.

This is my schema:

var mongoose = require('mongoose'),
Schema = mongoose.Schema;

var bimSchema = new Schema({
projectId: Number,
user: String,
items:[
{
bimObjectId: Number,
typeId: String,
position:{
floor: String,
room:{
name: String,
number: String
}
}
}
]
});

mongoose.model('bim', bimSchema);

I don't want the items array included in my rest call.

You use projection. The first example in the [mongoose query docs](

[To see links please register here]

) has a projection operation tucked in.

NB: not real code b/c I highlighted the important bits with triple stars

// find each person with a last name matching 'Ghost', ***selecting the `name` and `occupation` fields***
Person.findOne({ 'name.last': 'Ghost' }, ***'name occupation'***, function (err, person) {
if (err) return handleError(err);
console.log('%s %s is a %s.', person.name.first, person.name.last, person.occupation) // Space Ghost is a talk show host.
})

The `Person` schema isn't specified but I think the example is clear enough.

`.Select()` method is used to select which fields are to be returned in the query result
```
let result = await MyModel.find({ user : "user" }).select('name lastname status')
```

With the help of ```.select()``` this is possible.
- If number of fields required are less from total fields then,
```.select('projectId user')``` can be used
- Else number of fields to be ignored are less from total fields then,
```.select('-items')``` can be used.

So for getting a field, simply, space separated string of fields can be passed and for ignoring the field, space separated string with "-" before the field can be used.

For [more documentation][1].


[1]:

[To see links please register here]

Mongoose provides multiple ways to project documents with [`find`][3], [`findOne`][2], and [`findById`][1].

### 1. Projection as String:

```javascript
// INCLUDE SPECIFIC FIELDS
// find user and return only name and phone fields
User.findOne({ email: email }, 'name phone');

// EXCLUDE SPECIFIC FIELD
// find user and return all fields except password
User.findOne({ email: email }, '-password');
```

### 2. Projection by passing `projection` property:

```javascript
// find user and return just _id field
User.findOne({ email: email }, {
projection: { _id: 1 }
});
```

### 3. Using [`.select`][4] method:

```javascript
// find user and return just _id and name field
User.findOne({ email: email }).select('name');

// find user and return all fields except _id
User.findOne({ email: email }).select({ _id: 0 });
```

You can do the same with [`find`][3] and [`findById`][1] methods too.


[1]:

[To see links please register here]

[2]:

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[3]:

[To see links please register here]

[4]:

[To see links please register here]

Find Specific properties also avoid some properties
```
await User.find({ email: email }, { name: 1, phone: 1, status: 1, password: 0 });
```

MyModel.find({name: "john"}, 'name age address', function(err, docs) {
console.log(docs);
});
This will return fields - `name`, `age` and `address` only.