Mongoose - How to select a specific object inside an array of a populated field in Mongoose?

Question

I have populated a virtual in Mongoose, the populated virtual will retrieve an array of objects.

 objects:{[name:'xxx',age:20],[name:'yyy',age:21],[name:'zzz', age:23]}

How do I make it that it only retrieves one element I specify?

...
.populate({
   path:'someVirtual',
   select:'objects', //get only the 'objects' array
   options: {where:'objects',elemMatch:{name:'zzz'}} //this is what I tried 
                                                     //but it doesn't work
  )}
 .exec(function(err,docs){
    //handle
  });

Dark Knight · Accepted Answer · 2018-06-24 15:11:42Z

1

You can use match inside populate

.populate({
   path:'someVirtual',
   match: { objects: { $elemMatch: { name: 'zzz' } } },
   select: 'objects'                                        
})

and if you want to use projection then

.populate({
   path:'someVirtual',
   match: { objects: { $elemMatch: { name: 'zzz' } } },
   select: { objects: { $elemMatch: { name: 'zzz' } } }                                   
})

edited Jun 24, 2018 at 15:11

answered Jun 24, 2018 at 15:01

Dark Knight

1,0936 gold badges26 silver badges50 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

ReconditusNeumen Over a year ago

It worked, thank you! This helped a lot, I tried reading the docs but I felt like the usage examples weren't clear. I hope they'd make it more detailed in the future.

Collectives™ on Stack Overflow

Mongoose - How to select a specific object inside an array of a populated field in Mongoose?

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related