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Databases Mongo Basics Go Further With Mongo Updating Data

Posted by Amelia Groen
Amelia Groen
6,144 Points

Using find() returns nothing with ObjectID

I've used db.posts.find({}, {_id: true}) and it fetches 4 records. 

db.posts.find({}, {_id: true})
{
  "_id": ObjectId("5b05471cbb36b738a23ed101")
}
{
  "_id": ObjectId("5b05471cbb36b738a23ed102")
}
{
  "_id": ObjectId("5b05471cbb36b738a23ed103")
}
{
  "_id": ObjectId("5b05471cbb36b738a23ed104")
}

When I copy one and type in

db.posts.find({author: ObjectId("5b05471cbb36b738a23ed104")})

however, I get the result of 'fetched 0 record(s) in 1ms' I can see the records, they're right there! Why isn't this method returning anything? What am I doing wrong here? I'm at a loss...

1 Answer

Adam Beer
Adam Beer
11,314 Points
Adam Beer
Adam Beer
11,314 Points

If your first step is "db.users.find({}, {_id: true})" and the second step "db.posts.find({author: ObjectId("5b05471cbb36b738a23ed104")})" then now what happends?

Amelia Groen
Amelia Groen
6,144 Points

Yes, that works! I didn't realise I needed to use 'users.find()' instead of 'posts.find()' in the first step! Thank you for helping :)

Adam Beer
Adam Beer
11,314 Points
Adam Beer
Adam Beer
11,314 Points

Your welcome! Happy coding!